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llc current - resonant off - line switching controller SSC3S921 data sheet SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 1 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 description the SSC3S921 is a controller with smz* method for llc current resonant switch ing power supplies , incorporating a floating drive circuit for a high - side power mosfet. the product includes useful functions such as st andby function , automatic dead time adjustment, and capacitive mode detection. the product achieves high efficiency , low noise and high cost - performance power supply systems with few external components. *smz: s oft - switched m ulti - resonant z ero current swi tch, achieved soft switching operation during all switching periods . features standby mode change function ? output power at light load: p o = 1 25 mw (p in = 0.27 w, as a reference with discharge resistor of 1m for across the line capacitor) ? burst operation in standby mode ? soft - on/soft - off function: reduces audible noise pfc ic on/off function: in standby operation, the ic turns off pfc ic. soft - start function capacitive mode detection function reset detection function automatic dead time adjustment function input electrolytic capacitor discharge function protection s ? brown - in and brown - out f unction : ? high - side driver uvlo : auto - restart : auto - restart ? overcurrent protection (ocp) : auto - restart, p eak drain current detection, 2 - step detection ? overload protection (olp) : auto - restart ? overvoltage protection (ovp ) : auto - restart ? reg overvoltage protection (reg_ovp ) : latched shutdown ? thermal shutdown (tsd) : auto - restart typical application package sop18 not to scale application s switching power supplies for electronic devices such as: digital appliances: lcd television and so forth office automation (oa) equipment : server, multi - function printer, and so forth industrial apparatus communication facilities a d j v s e n v c c f b s t v g h v s v b r e g c s s c l p l v g l g n d r c s b v o u t 2 ( + ) v o u t ( - ) v o u t 1 ( + ) 1 1 5 1 6 1 7 1 8 4 3 2 u 1 s s c 3 s 9 2 1 7 6 5 1 2 1 3 1 4 9 8 1 0 1 1 t c _ s s c 3 s 9 2 1 _ 1 _ r 4 p f c o u t v c c g n d p f c i c ( s s c 2 0 1 6 s )
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 2 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 c ontents description -------------------------------- -------------------------------- -------------------------------- ------ 1 contents -------------------------------- -------------------------------- -------------------------------- --------- 2 1. absolute maximum rati ngs -------------------------------- -------------------------------- ------------- 3 2. electrical characteristics -------------------------------- -------------------------------- ---------------- 4 3. block diagram -------------------------------- -------------------------------- ----------------------------- 7 4. pin configuration definitions -------------------------------- -------------------------------- ----------- 7 5. typical application -------------------------------- -------------------------------- ----------------------- 8 6. external dimensions -------------------------------- -------------------------------- ---------------------- 9 7. marking diagram -------------------------------- -------------------------------- ------------------------- 9 8. operational description -------------------------------- -------------------------------- --------------- 10 8.1 re sonant circuit operation -------------------------------- -------------------------------- ----- 1 0 8.2 startup operation -------------------------------- -------------------------------- ----------------- 13 8.3 undervoltage lockout (uvlo) -------------------------------- -------------------------------- 14 8.4 bias assist function -------------------------------- -------------------------------- --------------- 14 8.5 soft start function -------------------------------- -------------------------------- ---------------- 14 8.6 minimum and maximum switching frequency setting -------------------------------- --- 15 8.7 high - side driver -------------------------------- -------------------------------- ------------------- 15 8.8 constant voltage control operation -------------------------------- -------------------------- 15 8.9 standby function -------------------------------- -------------------------------- ------------------ 16 8.9.1 standby mode changed by external signal -------------------------------- ----------- 16 8.9.2 burst oscillation operation -------------------------------- ------------------------------- 17 8.9.3 pfc on/off function -------------------------------- -------------------------------- ---- 17 8.10 automatic dead time adjustment function -------------------------------- ---------------- 17 8.11 brown - in and brown - out function -------------------------------- --------------------------- 18 8.12 capacitive mode detection function -------------------------------- -------------------------- 19 8.13 input electrolytic capacitor discharge function -------------------------------- ----------- 20 8.14 reset detection function -------------------------------- -------------------------------- -------- 20 8. 15 overvoltage protection (ovp) -------------------------------- -------------------------------- -- 22 8.16 reg overvoltage protection (reg_ovp) -------------------------------- ------------------- 22 8.17 overcurrent protection (ocp) -------------------------------- -------------------------------- - 22 8.18 overload protection (olp) -------------------------------- -------------------------------- ------ 23 8. 19 thermal shutdown (tsd) -------------------------------- -------------------------------- ------- 23 9. design notes -------------------------------- -------------------------------- ------------------------------ 24 9.1 external components -------------------------------- -------------------------------- ------------ 24 9.1.1 in put and output electrolytic capacitors -------------------------------- -------------- 24 9.1.2 resonant transformer -------------------------------- -------------------------------- ----- 24 9.1.3 current detection resistor, r ocp -------------------------------- ------------------------ 24 9.1.4 current resonant capacitor, ci -------------------------------- ------------------------- 24 9.1.5 gate pin peripheral circuit -------------------------------- ------------------------------- 24 9.2 pcb trace layout and component placement -------------------------------- ------------- 24 10. pattern layout example -------------------------------- -------------------------------- --------------- 26 important notes -------------------------------- -------------------------------- ------------------------------ 28
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 3 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 1. absolute maximum ratings current polarities are defined as follows: current going into the ic (sinking) is positive current (+); and current coming out of the ic (sourcing) is negative current (?). unless otherwise specified, t a is 25c . characteristic symbol pins rating unit vsen pin sink current i sen 1 ? cc 2 ? ? fb 3 ? ? adj 4 ? ? reg v css pin voltage v css 5 ? ? cl 6 ? ? rc 7 ? ? pl 8 ? ? sb 9 ? gl 11 C ? reg + 0.3 v reg pin source current i reg 12 C ? b C s 14 ? ? s 15 ? ? gh 16 ? s ? b + 0.3 v st pin voltage v st 18 ? ? op ? stg ? j
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 4 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 2. electrical characteristics current polarities are defined as follows: current going into the ic (sinking) is positive current (+); and current coming out of the ic (sourcing) is negative current (?). unless otherwise specified, t a is 25c , v cc is 19 v . characteristic symbol conditions pins min. typ. max. unit start circuit and circuit current operation start voltage v cc(on) 2 ? cc(off) 2 ? v startup current biasing threshold voltage * v cc(bias) 2 ? 9.8 10.6 v circuit current in operation i cc(on) 2 ? cc(off) v cc = 11 v 2 ? cc(st) 18 ? cc ( p.off ) 2 ? 8.9 9.8 v reg pin overvoltage protection release threshold voltage v cc ( l.off ) 2 ? 5.0 8.0 v circuit current in protection i cc(p) v cc = 10 v 2 ? oscillator minimum f requency f (min) 11 C ? (max) 11 C ? d(min) 11 C ? d(max) 11 C ? (min)adj1 r css = 30 k 11 C ? 73 77 khz externally adjusted minimum f requency 2 f (min)adj2 r css = 77 k 11 C ? 45.4 48.4 khz feedback control fb p i n oscillation start threshold voltage v fb(on) 3 C fb(off) 3 C fb(max) v fb = 0 v 3 C ? ? ? fb(r) 3 C soft - start css pin charging current i css(c) 5 C ? ? ? css(r) v cc = 11v 5 C (max)ss 11 C ? standby sb pin standby threshold voltage v sb(stb) 9 C sb(on) 9 C v cc(off ) = v cc(p.off) < v cc(bias) always.
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 5 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 characteristic symbol conditions pins min. typ. max. unit sb pin oscillation stop threshold voltage v sb(off) 9 C 10 0.4 0.5 0.6 v sb pin clamp voltage v sb(clamp) 9 C 10 7 8.5 10 v sb pin source current i sb(src) 9 C 10 ? 17 ? 10 ? 3 a sb pin sink current i sb(snk) 9 C 10 3 10 17 a css pin standby release threshold voltage v css(stb) 5 C 10 1.35 1.50 1.65 v pfc on/of function adj pin voltage in normal operation v adj(l) i adj = 100 a 4 C 10 0 1 2 v adj pin voltage in standby operation v adj(h) i adj = ? 100 a 4 C 10 8.5 9.9 10.8 v overload protection (olp) cl pin olp threshold voltage v cl(olp) 6 C 10 3.9 4. 2 4.5 v cl pin source current i cl(src) 6 C 10 ? 29 ? 17 ? 5 a brown - in and brown - out vsen pin threshold voltage (on) v sen(on) 1 C 10 1.248 1.300 1.352 v vsen pin threshold voltage (off) v sen(off) 1 C 10 1.056 1.100 1.144 v vsen pin clamp voltage v sen (clamp) 1 C 10 10.0 v reset detection maximum reset time t rst(max) 11 C 10 16 ? 15 4 5 6 s driver circuit power supply vreg pin output voltage v reg 12 C 10 9.6 10.0 10.8 v high - side driver high - side driver operation start voltage v buv(on) 14 C 15 5.7 6.8 7.9 v high - side driver operation stop voltage v buv(off) 14 C 15 5.5 6.4 7.3 v driver circuit vgl,vgh pin source current 1 i gl(src)1 i gh(src)1 v reg = 10.5v v b = 10.5v v gl = 0v v gh = 0v 11 C 10 16 ? 15 C 540 ma vgl,vgh pin sink current 1 i gl(snk)1 i gh(snk)1 v reg = 10.5v v b = 10.5v v gl = 10.5v v gh = 10.5v 11 C 10 16 ? 15 1.50 a vgl,vgh pin source current 2 i gl(src)2 i gh(src)2 v reg = 11.5v v b = 11.5v v gl = 10v v gh = 10v 11 C 10 16 ? 15 ? 140 ? 90 ? 40 ma vgl,vgh pin sink current 2 i gl(snk)2 i gh(snk)2 v reg = 12v v b = 12v v gl = 1.5v v gh = 1.5v 11 C 10 16 ? 15 140 230 360 ma current resonant and overcurrent protection (ocp) capacitive mode detection voltage 1 v rc1 7 C 10 0.02 0.10 0.18 v ? 0.18 ? 0.10 ? 0.02 v capacitive mode detection voltage 2 v rc2 7 C 10 0.4 0.50 0.6 v
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 6 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 characteristic symbol conditions pins min. typ. max. unit ? 0.6 ? 0.50 ? 0.4 v rc pin threshold voltage (low) v rc(l) 7 C 10 1.42 1.50 1.58 v ? 1.58 ? 1.50 ? 1.42 v rc pin threshold voltage (high speed) v rc(s) 7 C 10 2.15 2.30 2.45 v ? 2.45 ? 2.30 ? 2.15 v css pin sink current (low) i css(l) 5 C 10 1.1 1.8 2.5 ma css pin sink current (high speed) i css(s) 5 C 10 13.0 20.5 28.0 ma overvoltage protection (ovp) vcc pin ovp threshold voltage v cc(ovp) 2 C 10 30.0 32.0 34.0 v reg pin ovp threshold voltage v cc(reg) 12 C 10 11.5 12.4 13.5 v thermal shutdown (tsd) thermal shutdown temperature t j(tsd) 140 c thermal resistance junction to ambient thermal resistance j - a 95 c /w
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 7 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 3. block diagram 4. pin configuration definitions number name function s 1 v sen t he mains input voltage detection signal input 2 v cc s upply voltage input for the ic, and over voltage protection (ovp) signal input 3 fb f eedback signal input for constant voltage control 4 adj pfc on/off signal output 5 c ss soft - start capacitor connection 6 cl load current detection capacitor connection 7 rc resonant current detection signal input, and overcurrent protection (ocp) signal input 8 pl resonant current detection signal input for olp 9 sb standby mode change signal input 10 gnd ground 11 vgl low - side gate drive output 12 r eg supply voltage output for gate drive circuit 13 ? (pin removed) 14 vb supply voltage input for high - side driver 15 vs floating ground for high - side driver 16 vgh high - side gate drive output 17 (nc) 18 st startup current input s t a r t u p s t a r t / s t o p / r e g / b i a s / o v p m a i n i n p u t s e n s e s t a n d b y c o n t r o l f b c o n t r o l f r e q . c o n t r o l d e a d t i m e u v l o l e v e l s h i f t o c d e t e c t o r r v d e t e c t o r r c d e t e c t o r p l d e t e c t o r / o l p f r e q . m a x s o f t - s t a r t / o c / f m i n a d j v c c g n d s t 1 8 2 1 0 1 9 3 5 1 4 1 6 1 5 7 6 8 4 1 1 1 2 v c c g n d v s e n s b f b c s s v b v g h v s r e g v g l r c c l p l a d j h i g h s i d e d r i v e r p f c o n / o f f b d _ s s c 3 s 9 2 1 _ r 3 1 2 3 4 5 6 7 8 9 1 8 1 6 1 5 1 4 1 2 1 1 1 0 v c c f b a d j c s s c l r c p l s b s t v g h v s v b r e g v g l g n d v s e n
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 8 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 5. typical application figure 5 - 1 typical application a d j v s e n v c c f b s t v g h v s v b r e g c s s c l p l v g l g n d r c s b s t a n d b y v o u t 2 ( + ) v o u t ( - ) v o u t 1 ( + ) t 1 p c 1 p c 2 p c 1 p c 2 1 1 5 1 6 1 7 1 8 4 3 2 u 1 s s c 3 s 9 2 1 7 6 5 1 2 1 3 1 4 9 8 1 0 1 1 c 1 r 2 r 3 r 4 c 4 c 5 r 5 c 7 c 8 r o c p r 6 r 7 r 8 r 1 r 1 0 r 1 1 r 1 2 r 1 3 r 1 4 r 1 5 r 1 6 r 1 7 q 1 q ( h ) q ( l ) c 2 c 3 c 9 c 1 0 c 1 1 c 1 2 d 1 d 3 d 4 d 5 d 6 c i c v d 5 1 d 5 2 d 5 3 d 5 4 c 5 1 c 5 2 c 5 3 c 5 4 c 5 5 r 5 1 r 5 2 r 5 3 r 5 4 r 5 6 r 5 5 r 5 7 r 5 8 r 5 9 q 5 1 c 6 t c _ s s c 3 s 9 2 1 _ 3 _ r 4 p f c o u t p f c i c ( s s c 2 0 1 6 s ) v c c g n d q c r a d j 1 r a d j 2 c a d j r 1 5 r 1 6
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 9 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 6. external dimensions sop1 8 7. marking diagram notes: dimension is in millimeters pb - free 1 1 8 p a r t n u m b e r s s c 3 s 9 2 1 x x x x c o n t r o l n u m b e r l o t n u m b e r y i s t h e l a s t d i g i t o f t h e y e a r ( 0 t o 9 ) m i s t h e m o n t h ( 1 t o 9 , o , n o r d ) d i s a p e r i o d o f d a y s ( 1 t o 3 ) : 1 : 1 s t t o 1 0 t h 2 : 1 1 t h t o 2 0 t h 3 : 2 1 t h t o 3 1 s t s k y m d
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 10 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 8. operational description all of the parameter values used in these descriptions are typical values, unless they are specified as minimum or maximum. current polarities are defined as follows: current going into the ic (sinking) is positive current (+); and current coming out of the ic (sourcing) is negative current (?). q (h) and q (l) indicate a high - side power mosfet a nd a low - side power mosfet respectively. ci and c v indicate a current resonant capacitor and a voltage resonant capacitor , respectively. 8.1 resonant circuit operation figure 8 - 1 shows a basic rlc series resonant circuit. the impedance of the circuit, ? , is as the following equation . is angular frequency ; and = 2f . t hus, fl = 1/2 fc , ? of equation ( 2 ) becomes the minimum value , r ( see figure 8 - 2 ). in the case, is calculated by equatio n ( 3 ) . ? becomes minimum value is called a resonant frequency, f 0 . t he higher frequency area than is an inductance area . t he lower frequency area than is a capacitance area. f rom equation ( 3 ) , is as follows: (h) and q (l) , are connec ted in series with v in . the series resonant circuit and the v oltage resonant capacitor , c v , are connected in parallel with q (l) . the series resonant circuit is consisted of the following components : the resonant inductor, l r ; the primary winding, p, of a t ransformer, t1 ; and the current resonant capacitor, c i . t he coupling between the primary and secondary winding s of t1 is designed to be poor so that the leakage inductance increases. this leakage inductance is us ed for l r . this results in a down sized of the series resonant circuit . the dotted mark with t1 describe s the winding polarity, the secondary windings , s1 and s2 , are connected so that the polarities are set to the same position as shown in figure 8 - 3 . i n addition, the winding numbers of each other should be equal. from equation ( 1 ) , the impedance of a current resonant power supply is calculated by equation ( 5 ) . from equation ( 4 ) , the resonant frequency, , is calculated by equation ( 6 ) . r is the inductance of the resonant inductor, l p is the inductance of the primary winding p, and ci is the capacitance of current resonant capacitor. figure 8 - 3 . current r esonant p ower s upply c ircuit r l c f 0 f r e q u e n c y i n d u c t a n c e a r e a c a p a c i t a n c e a r e a i m p e d a n c e r c v c i l r q ( h ) p s e r i e s r e s o n a n t c i r c u i t t 1 s 1 s 2 v o u t ( + ) ( ? ) v i n v g h v g l q ( l ) v d s ( l ) v d s ( h ) v c i i d ( h ) i d ( l ) i c i i s 2 i s 1 l p
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 11 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 in the current resonant power supply, q (h) and q (l) are alternatively turned on and off. the on and off time s of them are equal. there is a dead time between the on period s of q (h) and q (l) . during the dead time, q (h) and q (l) are in off status. in t he current resonant power supply , the frequency is controlled. when the output voltage decreases , the ic decreases the switching frequency so that the output power is increased to keep a constant output voltag e . this must be control led in the inductance area ( ). since the winding current is delayed from the winding voltage in the inductance area, the turn - on oper ates in a z cs (zero current switching) ; and the turn - off operates in a zvs (zero voltage switching) . thus, the switching loss es of q (h) and q (l) are nearly zero . in the capacitance area ( ), the current resonant power supply operates as follows : when t he output voltage decreases, the switching frequency is decreased ; and then , the output power is more decreased. th erefore , the output voltage cannot be kept c onstant . since the winding current goes ahead of the winding voltage in the capacitance ar ea, q (h) and q (l ) operate in the hard switching . this results in the increase s of a power loss . this operation in the capacitance area is called the capacitive mode operation. the current resonant power supply must be operated without the c apacitive mode o peration ( for more detail s , see section 8.12 ). figure 8 - 4 describe s the basic operation waveform of current resonant power supply (see figure 8 - 3 about the symbol in figure 8 - 4 ). for the description of current resonant waveforms in normal operation , the operation is separate d into a period a to f . in the following description : i d(h) is the current of q (h) , i d(l) is the current of q (l) , v f(h) is the forwerd voltage of q (h) , v f( l ) is the forwerd voltage of q ( l ) , i l is the current of l r , v in is an input voltage , v ci is ci voltage , and v cv is c v voltage . the current resonant power supply operations in period a to f are as follows: 1) period a when q (h) is on , an energy is stored into the series resonant circuit by i d(h) that flow s through the resonant circuit and the transformer (see figure 8 - 5 ) . at the same time, the e nergy is transferred to the secondary circuit. when the primary winding voltage can not keep the on status of the secondary rectifier, the energy transmittion to the secondary circuit is stopped. 2) period b after the secondary side current becomes zero, the resonant current flows to the primary side only to charge ci (see figure 8 - 6 ) . figure 8 - 4 . the basic operation waveforms of current resonant power supply figure 8 - 5 . operation in period a figure 8 - 6 . operation in period b i d ( l ) i d ( h ) i s 1 v g l v g h v d s ( l ) i c i v c i i s 2 a b c d e f v i n + v f ( h ) v d s ( h ) v i n c v c i l r q ( h ) q ( l ) l p o n o f f i d ( h ) v i n s 1 s 2 i s 1 v c v v c i c v c i l r q ( h ) q ( l ) l p o n o f f i d ( h ) v i n s 1 s 2
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 12 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 3) period c c is the dead - time period . q (h) and q (l) are in off status . when q (h) turns off, c v is discharged by i l that is supplied by the energy stored in the series resonant circuit appl ies (see figure 8 - 7 ) . when v cv decreases to v f(l) , ?i d(l) flows through the body diode of q (l) ; and v cv is clamped to v f(l) . after that, q (l) turns on. since v ds(l) is nearly zero at the point, q (l) operates in the zvs and the zcs ; thus, the switching loss achieves nearly zero. 4) period d when q (l) turns on , i d(l) flows as shown in figure 8 - 8 ; and v ci is appl ied t he primary winding voltage of the transformer . at the same time, e nergy is transferred to the secondary circuit. when the primary winding voltage can not keep the on stat us of th e secondary rectifier , the energy transmittion to the secondary circuit is stopped. 5) period e after the secondary side current becomes zero, the resonant current flows to the primary side only to charge ci (see figure 8 - 9 ) . 6) period f f is the dead - time period . q (h) and q (l) are in off status . when q ( l ) turns off, c v is charged by ? i l that is supplied by the energy stored in the series resonant circuit appl ies (see figure 8 - 10 ) . when v cv decreases to v in + v f(h) , ?i d( h ) flows through body diode of q ( h ) ; and v cv is clamped to v in + v f(h) . after that, q ( h ) turns on. since v ds( h ) is nearly zero at the point, q ( h ) operates in the zvs and the zcs ; thus, the switching loss achieves nearly zero. after the p eriod f , i d( h ) flows again; and the operation returns to the period a. the above operatio n is repeated to transfer energy to the secondary side from the resonant circuit. figure 8 - 7 . operation in period c figure 8 - 8 . operation in period d figure 8 - 9 . operation in period e figure 8 - 10 . operation in period f c v c i l r q ( h ) q ( l ) l p o f f o f f i l v i n - i d ( l ) v c v c v c i l r q ( h ) q ( l ) l p o f f o n v i n i d ( l ) i s 2 s 1 s 2 v c i c v c i l r q ( h ) q ( l ) l p o f f o n v i n i d ( l ) s 1 s 2 c v c i l r q ( h ) q ( l ) l p o f f o f f - i l v i n - i d ( h ) v c v
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 13 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 8.2 startup operation figure 8 - 11 shows the vcc pin peripheral circuit. figure 8 - 12 shows the startup operational waveforms. the power supply starts as follows: 1) the mains input voltage is provided, and the vsen pin voltage increases to the on - threshold voltage, v sen(on) = 1.300 v, or more. 2) t he s tartup c urrent, i st , which is a constant current of 6.0 ma is provided from the ic to capacitor c2 connected to the vcc pin, c2 is charged . 3) c adj is charged by i adj = ? 10a to increase the adj pin voltage. 4) when the vcc pin voltage increases to the operati on start voltage, v cc(on) = 17.0 v, the reg pin voltage is output. at the same time, the adj pin outputs the pfc on signal, and the pfc control ic is activated. t he vcc pin voltage is decreased by the power dissipation of the ic. 5) when the vcc pin voltage decreases to v cc(bias) = 9.8 v, the c9 connected to fb pin starts to be charged. when the fb pin voltage increases to the oscillation start threshold voltage, v fb(on) = 0.30 v, or more, the sw iching operation starts. after that, the startup circuit stops automatically, in order to eliminate its own power consumption. during the ic operation, the rectified voltage from the auxiliary winding voltage, v d , in figure 8 - 11 is a power source to the vcc pin. the winding turns of the winding d should be adjusted so that the vcc pin voltage is applied to equation ( 7 ) within the specification of the mains input voltage range and output load range of the power supply. the target voltage of the winding d is about 1 9 v. ? cc < 32.0 (v) ( 7 ) the startup time, t start , is determined by the value of c2 and c6 connected to the css pin. since the startup time for c6 is much smaller than that for c2, the startup time is approximately given as below: start is the startup time in s, v cc(int) is the initial voltage of the vcc pin in v , and i cc(st) is the startup current, 6.0 ma figure 8 - 11 . vcc pin peripheral circuit figure 8 - 12 . startup operation when pfc on/off function is enabled 10 2 vcc gnd u 1 r 4 vsen c 4 r 2 r 3 c 2 1 st d 1 18 v d r 1 fb 3 c 9 r 8 pc 1 c 1 v cc q c r adj 1 r adj 2 d adj vac d st 1 c x l 1 d st 2 ssc 2016 s u 2 adj r st 4 reg 12 c adj i adj css 5 c 6 r 5 vcc pin voltage v cc ( on ) v cc ( bias ) reg pin voltage fb pin voltage vgl pin voltage v reg 0 0 0 0 v fb ( on ) vsen pin voltage 0 v sen ( on ) adj pin voltage 0 charged by i adj pfc on signal output
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 14 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 8.3 undervoltage lockout (uvlo) figure 8 - 13 shows the relationship of v cc and i cc . after the ic starts operation, when the vcc pin voltage decreases to v cc(off) = 8.9 v, the ic stops switching operation by the undervoltage lockout (uvlo) function and reverts to the state before startup again. figure 8 - 13 . v cc versus i cc 8.4 bias assist function figure 8 - 14 shows the vcc pin voltage behavior during the startup period. figure 8 - 14 . v cc pin voltage during startup period when the conditions of section 8.2 are fulfilled, the ic starts operation. thus, the circuit current, i cc , increases, and the vcc pin voltage begins dropping. at the same time, the auxiliary winding voltage, v d , increases in proportion to the output voltage rise. thus, the vcc pin voltage is set by the balance between dropping due to the increase of i cc and rising due to the increase of the auxiliary winding voltage, v d . when the vcc pin voltage decreases to v cc(off) = 8.9 v , the ic stops switching operation and a startup failure occurs. in order to prevent this, when the vcc pin voltage decreases to the s tartup c urrent t hreshold b iasing v oltage, v cc(bias) = 9.8 v, the bias assist f unction is activated . while the bias assist f unction is activated, any decrease of the vcc pin voltage is counteracted by providing the s tartup c urrent, i cc(st) , from the startup circuit. it is necessary to check the startup process based on actual operation in the application, and a djust the vcc pin voltage, so that the startup failure does not occur. if vcc pin voltage decreases to v cc(bias) and the bias assist function is activated, the power loss increases. thus, vcc pin voltage in normal operation should be set more than v cc(bias) by the following adjustments. t he turns ratio of the auxiliary winding to the secondary - side winding is increased. the value of c2 in figure 8 - 11 is increased and/or the value of r1 is reduced. during all protection operation, the bias assist function is disabled. 8.5 soft start function figure 8 - 15 shows the soft - start operation waveforms. figure 8 - 15 . soft - start operation the ic has soft start function to reduce stress of peripheral component and prevent the c apacitive mode operation . during the soft start operation , c 6 connected to the css pin is charged by the css pin charge current, i css(c) = ? 105 a . the o scillation frequency is varied by the css pin voltage. the switching frequency gradually decreases from f (max)ss * = 500 khz at most, according to the css pin voltage rise. at same time, output power increase s . when the output voltage increases, the ic is * the maximum frequency during normal operation is f (max) = 300 khz. i c c v c c o f f v c c o n v c c p i n v o l t a g e s t a r t s t o p i c s t a r t u p v c c p i n v o l t a g e v c c ( o n ) v c c ( b i a s ) v c c ( o f f ) s t a r t u p f a i l u r e s t a r t u p s u c c e s s t a r g e t o p e r a t i n g v o l t a g e t i m e b i a s a s s i s t p e r i o d i n c r e a s i n g b y o u t p u t v o l t a g e r i s i n g c s s p i n v o l t a g e p r i m a r y - s i d e w i n d i n g c u r r e n t 0 0 o c p l i m i t c 6 i s c h a r g e d b y i c s s ( c ) t i m e t i m e s o f t - s t a r t p e r i o d o c p o p e r a t i o n p e r o p d f r e q u e n c y c o n t r o l b y f e e d b a c k s i g n a l
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 15 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 operated with an oscillation frequency controlled by feedback. when the ic becomes any of the following conditions, c 6 is discharged by the css pin reset current, i css(r) = 1.8 ma. the vcc pin voltage decreases to the operation stop voltage, v cc(off) = 8.9 v, or less. the vsen pin voltage decreases to the off - threshold voltage, v sen(off) = 1.100 v, or less. any of protection operations in protection mode (ovp, olp or tsd) is activated. 8.6 minimum and maximum switching frequency setting the minimum switching frequency is adjustable by the value of r5 (r css ) connected to the css pin. the relationship of r5 (r css ) and the externally adjusted minimum frequency, f (min)adj , is shown in figure 8 - 16 . the f (min)adj should be adjusted to more than the resonant frequency, f o , under the condition of the minimum mains input voltage and the maximum output power. the maximum switching frequency , f max , is determined by the inductance and the capacitance of the resonant circuit. the f max should be adjusted to less than the maximum frequency, f (max) = 300 khz. figure 8 - 16 . r5 (r css ) versus f (min)adj 8.7 high - side driver figure 8 - 17 shows a bootstrap circuit. the bootstrap circuit is for driving to q (h) and is made by d 3 , r 12 and c 12 between the reg pin and the vs pin . when q (h) is off state and q (l) is on state, the vs pin voltage becomes about ground level and c 12 is charged from the reg pin. when the voltage of between the vb pin and the vs pin, v b - s , increases to v buv(on) = 6.8 v or more, an internal high - side drive circuit starts operation. when v b - s decreases to v buv(off) = 6.4 v or less, its drive circuit stops operation. in case the both ends of c 12 and d4 are short, the ic is protected by v buv(off) . d4 for protection against negative voltage of the vs pin figure 8 - 17 . bootstrap circuit d3 d3 should be an ultrafast recovery diode of short recovery time and low reverse current. when the maximum mains input voltage of the apprication is 265vac, it is recommended to use ultrafast recovery diode of v rm = 600 v c11, c12, and r12 the values of c11, c12, and r12 are determined by total gate charge, qg, of external mosfet and voltage dip amount between the vb pin and the vs pin in the burst mode of the standby mode change. c11, c12, and r12 should be adjust ed so that the voltage between the vb pin and the vs is more than v buv( on ) = 6.8 v by measuring the voltage with a high - voltage differential probe. t he reference value of c11 is 0.47 f to 1 f. the time constant of c12 and r12 should be less than 500 ns. the values of c12 and r22 are 0.047 f to 0.1 f, and 2.2 to 10 . c11 and c1 2 should be a film type or ceramic capacitor of low esr and low leak age current . d4 d4 should be a schottky diode of low forward voltage, v f , so that the voltage between the vb pin and the vs pin must not decrease to the absolute maximum ratings of ? 0.3 v or less. 8.8 constant voltage control operation figure 8 - 18 shows the fb pin peripheral circuit. the fb pin is sunk the feedback current by the photo - coupler , 40 50 60 70 80 20 30 40 50 60 70 80 f (m i n)adj (khz) r css (k ) SSC3S921_r2 v g h v s v b r e g v g l g n d t 1 1 5 1 6 u 1 1 2 1 4 1 0 1 1 r 1 2 d 3 c 1 1 c 1 2 d 4 b o o t s t r a p c i r c u i t q ( h ) q ( l ) c v c i
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 16 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 pc1, connected to fb pin. as a result, since the oscillation frequency is cont rolled by the fb pin, the output voltage is controlled to constant voltage (in inductance area). the feedback current increases under slight load condition , and thus the fb pin voltage decreases. while the fb pin voltage decreases to the oscillation stop t hreshold voltage, v fb(off) = 0.20 v, or less, the ic stops switching operation. this operation reduces switching loss , and prevents the increasing of the secondary output voltage. in figure 8 - 18 , r8 and c9 are for phase compensation adjustment, and c5 is for high frequency noise rejection.the secondary - side circu it should be designed so that the collector current of pc1 is more than 195 a which is the absolute value of the maximum source current, i fb(max) . especia lly the current transfer ratio, ctr, of the photo coupler should be taken aging degradation into consideration. figure 8 - 18 . fb pin peripheral circuit 8.9 standby function the ic has the standby function in order to increase circuit efficiency in light load. when the standby function is activated, the ic operates in the burst oscillation mode as shown in figure 8 - 19 . figure 8 - 19 . standby waveform the burst oscillation has periodic non - switching intervals . thus, the b urst mode reduces switching losses . generally, to improve efficiency under light load conditions, the frequency of the burst mode becomes just a few kilohertz. in addition , the ic has the soft - on and the soft - off function in order to suppress rapid and sharp fluctuation of the drain current during the burst mode. thus, the audible noises can be reduced ( see section 8.9.2 ). the operation of the ic changes to the standb y operation by the external signal ( see section 8.9.1 ). 8.9.1 standby mode changed by external signal figure 8 - 20 shows the standby mode change circuit with external signal. figure 8 - 21 shows the s tandby change operation waveforms. when the standby terminal of figure 8 - 20 is provided with the l signal, q1 turns off, c10 connected to the sb pin is discharged by the sink current, i sb(snk) = 10 a, and the sb pin voltage decreases. when the sb pin voltage decrease to the sb pin oscillation stop threshold vo ltage , v sb(off) = 0.5 v, t he operation of the ic is changed to the standby mode. when sb pin voltage is v sb(off) = 0.5 v or le ss and fb pin voltage is oscillation stop threshold voltage v fb(off) = 0.20 v or less, the ic stops switching operation. when the standby terminal is provided with the h signal and the sb pin voltage increases to standby threshold voltage v sb(stb) = 5.0 v or more, the ic returns to normal operation. figure 8 - 20 . standby mode change circuit figure 8 - 21 . standby change operation waveforms 3 10 fb gnd u 1 c 5 pc 1 c 9 r 8 t i m e p r i m a r y - s i d e m a i n w i n d i n g c u r r e n t n o n - s w i t c h i n g p e r i o d s w i t c h i n g p e r i o d s o f t - o n s o f t - o f f s t a n d b y u 1 g n d r e g s b f b p c 1 p c 2 p c 2 q 1 r 1 6 r 1 7 r 1 5 r 8 c 9 c 1 0 c 5 r 5 8 r 5 9 q 5 1 c 1 1 1 2 9 3 t i m e s t a n d b y s b p i n v o l t a g e p r i m a r y - s i d e m a i n w i n d i n g c u r r e n t v s b ( s t b ) s t a n d b y o p e r a t i o n 0 0 0 f b p i n v o l t a g e v f b ( o f f ) 0 s w i t c h i n g s t o p d i s c h a r g i n g b y i s b ( s n k ) v s b ( o f f ) h l h
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 17 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 8.9.2 burst oscillation operation in stan dby operation, the ic operates burst oscillation where the peak drain current is suppressed by soft - on /soft - off function in order to reduce audible noise from transformer. during burst oscillation operation, the switching oscillation is controlled by sb p in voltage. figure 8 - 22 shows the burst oscillation operation waveforms. figure 8 - 22 . burst oscillation operation waveforms when the sb pin voltage decreases to v sb(off) = 0.5 v or less and the fb pin voltage decreases to v fb(off) = 0.20 v or less, the ic stops switching operation and the output voltage decreases. since the output voltage decreases, the fb pin voltage increases. when the fb pin voltage increases to the oscillation start threshold voltage , v fb(on) = 0.30 v, c10 is charged by i sb(src) = ? 10 a , and the sb pin voltage gradually increases. when the sb pin voltage increases to the oscillation start threshold voltage, v sb(on) = 0.6 v, the ic resumes switching operation, controlling the frequency control by the sb pin voltage. thus, the output voltage increases (soft - on). after that, when fb pin voltage decrease to o s cillation s top t hreshold v oltage , v fb(off) = 0.20 v, c10 is discharged by i sb(snk) = 10 a and sb pin voltage decreases. when the sb pin voltage decreas es to v sb(off) again, the ic stops switching operation. thus, the output voltage decreases (soft - off) . t he sb pin discharge time in the soft - on and soft - off function depends on c10. when the value of c10 increases, the soft - on/soft - off function makes the p eak drain current suppressed, and makes the burst period longer. t hus, the output ripple voltage may increase and/or the vcc pin voltage may decrease. if the vcc pin voltage decreases to v cc(bias) = 9.8 v , the bias assist function is always activated , and it results in the increase of power loss ( see section 8.4 ) . thus, it is necessary to adjust the value of c10 while checking the input power, the output ripple voltage, and the vcc pin voltage. the reference value of c10 is about 0.0 01 f to 0.1 f. 8.9.3 pfc on/off function figure 8 - 23 shows the operational waveform of pfc on/off output function. when output power decreases and sb pin voltage reaches to v sb(off) = 0.5 v, the pfc on/off function activates and adj pin voltage increases to adj pin voltage in standby operation , v adj(h) = v reg = 10.0 v. when output power increases and sb pin voltage reaches to v sb(stb) = 5.0 v, the adj pin voltage decreases to adj pin voltage in normal operation, v adj(l) = 1 v. using the signal, the power supply of pfc control ic can be turned on/off when the ic becomes standby operation. when the operation starting voltage of pfc ic, v cc(on)_pfc , is less than v reg , the pfc circuit on/off system can be realized by low component count as shown in figure 8 - 24 . ssc2016s that is sanken pfc control ic is recommended . figure 8 - 23 . pfc on/off function figure 8 - 24 . typical circuit that pfc ic is stopped by the adj pin signal (v cc(on)_pfc < v reg ) 8.10 automatic dead time adjustment function the dead time is the period when both the high - side and the low - side power mosfets are off. as shown in figure 8 - 25 , if the dead time is shorter than the voltage resonant period, the power mosfet is t i m e o u t p u t v o l t a g e s b p i n v o l t a g e p r i m a r y - s i d e m a i n w i n d i n g c u r r e n t 0 0 0 f b p i n v o l t a g e v f b ( o f f ) 0 d i s c h a r g e d b y i s b ( s n k ) v f b ( o n ) v s b ( o f f ) v s b ( o n ) o u t p u t c u r r e n t 0 c h a r g e d b y i s b ( s r c ) s o f t - o f f s o f t - o n s b p i n v o l t a g e v s b ( s t b ) s t a n d b y o p e r a t i o n 0 a d j p i n v o l t a g e v r e g 0 v s b ( o f f ) r e g 1 2 u 1 a d j g n d p f c i c ( s s c 2 0 1 6 s ) v c c g n d 4 1 0 q c r a d j 1 r a d j 2
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 18 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 turned on and off during the voltage resonant operation. in this case, the power mosfet turned on and off in hard switching operation , and t he switching loss increase s . the automatic dead time adjustment function is the function that t he zvs (zero voltage switching) operation of q (h) and q (l) is controlled automatically by the voltage resonant period detection of ic . the voltage resonant period is varied by the power supply specifications (input voltage and output power, etc . ). however, the power supply with this function is un necessary to adjust the dead time for each power supply specification. figure 8 - 25 . zvs failure operation waveform as shown in figure 8 - 26 , the vs pin detects the dv/dt period of rising and falling of the voltage between drain and source of the low - side power mosfet, v ds(l) , and the ic sets its dead time to that period. this function controls so that the high - side and the low - side power mosfets are automatically switched to zero voltage switching (zvs) operation. this func tion operates in the period from t d(min) = 0.24 s to t d(max) = 1.65 s. i n minimum output power at maximum input voltage and maximum output power at minimum input voltage, the zcs (zero current switching) operation of ic ( the drain current flows through the body diode is about 600 n s as shown in figure 8 - 27 ) , should be checked based on actual operation in the application. figure 8 - 26 . vs pin and dead time period figure 8 - 27 . zcs check point 8.11 brown - in and brown - out function figure 8 - 28 shows the vsen pin peripheral circuit. this function detects the mains input voltage, and stops switching operation during low mains input voltage, to prevent exceeding input current and overheating. r2 to r4 set the detection voltage of this function. when the vcc pin voltage is higher than v cc(on) , t his function operates depending on the vsen pin voltage as follows: when the vsen pin voltage is more than v sen (on) = 1.300 v, the ic starts. when the vsen pin voltage is less than v sen (off) = 1.100 v, the ic stops switching operation. figure 8 - 28 . vsen pin peripheral circuit given, the dc input voltage when the ic starts as v in(on) , the dc input voltage when the switching operation of the ic stops a s v in(off) . v in(on) is calculated by equation ( 9 ) . v in( off ) is calculated by equation ( 10 ) . thus, t he relationship between v in(on) and v in(off) is equation ( 11 ) . q ( l ) d - s voltage , v ds ( l ) vgl vgh voltage resonant period loss increase by hard switching operation dead time t 1 c v c i v s v g l v g h g n d u 1 1 5 1 1 1 0 1 6 m a i n r v d e t e c t o r d v d t d t o n o n o f f v d s ( l ) l o w - s i d e , v d s ( l ) d e a d t i m e p e r i o d q ( h ) d r a i n c u r r e n t , i d ( h ) f l o w s t h r o u g h b o d y d i o d e a b o u t 6 0 0 n s 1 0 g n d u 1 r 4 v s e n c 4 r 2 r 3 c 1 1 v a c v d c
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 19 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 the detection resistance is calculated from equation ( 9 ) as follows: select a resistor designed against electromigration according to the requirement of the application, or use a combination of resistors in series for that to reduce each applied voltage the reference value of r2 is about 10 m . c 4 shown in figure 8 - 28 is for reducing rippl e voltage of detection voltage and making delay time. the value is 0.1 f or more, and the reference value is about 0.47 f. the value of r 2, r3 and r 4 and c 4 should be selected based on actual operation in the application. 8.12 capacitive mode detection functi on the resonant power supply is operated in the inductance area shown in figure 8 - 29 . in the capacitance area, the power supply becomes the c apacitive m ode operation ( see section 8.1 ). in order to prevent the operation , the minimum oscillation frequency is needed to be set higher than f 0 on each power supply specification . however, the ic has the c apacitive mode operation detection function kept the frequency higher than f 0 . thus, the minimum oscillation frequency setting is unnecessary and the pow er supply design is easier. in addition, the ability of transf ormer is improve d because the operating frequency can operate close to the resonant frequency, f 0 . the resonant current is detected by the rc pin, and the ic prevents the capacitive mode operation. when the capacitive mode is detected, the c7 connected to cl pin is charged by i cl(src) = ? 17 a. when the cl pin voltage increases to v cl(olp) , the olp is activated and the switching operation stops. during the olp operation, the intermittent operation by uvlo is repeated ( see section 8.18 ). the detection voltage is changed to v rc1 = 0.10 v or v rc2 = 0.50 v dependin g on the load as shown in figure 8 - 31 and figure 8 - 32 . the capaciti ve mode o peration d etection f unction operations as follows: period in which the q (h) is on figure 8 - 30 shows the rc pin waveform in the inductance area, and figure 8 - 31 and figure 8 - 32 shows the rc pin waveform in the capacitance area. in the inductance area , the rc pin voltage doesn t cross the plus side detection voltage in the downward direction during the on period of q (h) as shown in figure 8 - 30 . on the contrary, in the capacitance are a, the rc pin voltage crosses the plus side detection voltage in the downward d irection. at this point, the capacitive mode operation is detected. thus, q (h) is turned off, and q (l) is turned on , as shown in figure 8 - 31 and figure 8 - 32 . period in which the q (l) is on contrary to the above of q (h) , in the capacitance are a, the rc pin voltage crosses the minus side detection voltage in the upward directiont during the on peri od of q ( l ) at this point, the capacitive mode operation is detected. thus, q ( l ) is turned off and q ( h ) is turned on . as above, since the c apacitive mode operation is detected by pulse - by - pulse and the operating frequency is synchronized with the frequency of the c apacitive mode operation, and the c apacitive mode operation is prevented. i n addition to the adjusting method of r ocp , c3, and r6 in section 1.1 , r ocp , c3, and r6 should be adjusted so that the absolute value of the rc pin voltage increases to more than |v rc 2 | = 0.50 v under the condition caused the capacitive mode operation easily, such as startup, turning off the mains input voltage, or output shorted. the rc pin voltage must be within the absolute maximum ratin gs of ? 6 to 6 v figure 8 - 29 . operating area of resonant power supply figure 8 - 30 . rc pin voltage in inductance area f 0 c a p a c i t a n c e a r e a i n d u c t a n c e a r e a o p e r a t i n g a r e a i m p e d a n c e r e s o n a n t f r e s u e n c y h a r d s w i t c h i n g s i f t s w i t c h i n g u n c o n t r o l l a b l e o p e r a t i o n 0 + v r c v d s ( h ) o n o f f r c p i n v o l t a g e
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 20 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 figure 8 - 31 . high side c apacitive mode detection in light load figure 8 - 32 . high side c apacitive mode detection in heavy load 8.13 input electrolytic capacitor discharge function figure 8 - 33 shows an application that residual volt age of the input capacitor, c1, is reduced after turning off the mains input voltage. r2 is connected to the ac input lines through d7 and d8. just after turning off the mains input voltage, the vsen pin voltage decreases to v sen(off) = 1.100 v according to a short time of the time constant with r2 to r4 and c4, and c1 is discharged by the equivalent to i cc(st) = 6.0 ma. figure 8 - 33 . input capacitor discharge 8.14 reset detection function in the startup period, the feedback control fo r the output voltage is inactive. if a magnetizing current may not be reset in the on - period because of unbalanced operation, a negative current may flow just before a power mosfet turns off. this causes a hard switching operation, increases the stresses of the power mosfet. where t he magnetizing current means the circulating current applied for resonant operation, and flows only into the primary - side circuit. to prevent t he hard switching, the ic has the r eset d etection f unction. figure 8 - 35 shows the high - side operation and the reference drain current waveform s in a normal resonant operation and a re set failure operation. to prevent the hard switching operation , t he r eset d etection f unction operates such as an on period is extend ed until the absolute value of a rc pin voltage, |v rc1 |, increases to 0.10 v or more . when the on period reaches the maximum reset time, t rst(max) = 5 s, the on - period expires at that moment, i.e., the power mosfet turns off (see figure 8 - 34 ). figure 8 - 34 . reset detection operation example at high - side on p eriod v d s ( h ) 0 0 c a p a c i t i v e m o d e o p e r a t i o n d e t e c t i o n o n o f f + v r c 2 r c p i n v o l t a g e + v r c 1 v d s ( h ) 0 0 c a p a c i t i v e m o d e o p e r a t i o n d e t e c t i o n o n o f f + v r c 2 r c p i n v o l t a g e + v r c 1 1 0 g n d u 1 r 4 v s e n c 4 r 2 r 3 c 1 1 m a i n i n p u t o f f d 7 d 8 s t 1 8 6 m a ( i c c ( s t ) ) 0 v rc = + 0 . 1 v expanded on - period i d ( h ) vgl pin voltage low high normal on - period t rst ( max ) reset failure waveform vgh pin voltage turning - on in negative drain current low high
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 21 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 figure 8 - 35 . reference high - side operation and drai n current waveform s in normal resonant operation and in reset failure operation i d ( h ) c v c i l r q ( h ) q ( l ) l p c v c i l r l p c v c i l r l p c v c i l r l p c v c i l r l p c v c i l r l p a b c e f 0 m a g n e t i z i n g c u r r e n t v d s ( h ) = 0 v v d s ( h ) = 0 v t u r n i n g o n a t v d s ( l ) = 0 v r e s u l t s i n s o f t - s w i t c h i n g v d s ( h ) = 0 v v d s ( h ) = 0 v t u r n i n g o n a t v d s ( l ) > > 0 v r e s u l t s i n h a r d - s w i t c h i n g r e c o v e r y c u r r e n t o f b o d y d i o d e p o i n t a p o i n t b p o i n t c p o i n t d p o i n t e p o i n t f o f f o f f o n o f f o f f o f f o f f o f f o n o f f o f f o n d i d ( h ) q ( h ) q ( l ) q ( h ) q ( l ) q ( h ) q ( l ) q ( h ) q ( l ) q ( h ) q ( l ) i d ( h ) i d ( h ) i d ( h ) i d ( h ) i d ( h ) n o r m a l r e s o n a n t o p e r a t i o n r e s e t f a i l u r e o p e r a t i o n
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 22 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 8.15 overvoltage protection (ovp) when the voltage between the vcc pin and the gnd pin is applied to the ovp t hreshold v oltage , v cc(ovp) = 32.0 v , or more, the over voltage p rotection (ovp) is activated, and the ic stops switching operation in protection mode. after stopping, the vcc pin voltage decreas es to v cc(off) = 8.9 v, the undervoltage lockout (uvlo) function is activated, and the ic reverts to the state before startup again . after that, the startup circu it is activated, the vcc pin voltage increases to v cc(on) = 17.0 v, and the ic restarts. during the protection mode, restart and stop are repeated. when the fault co ndition is removed, the ic returns to normal operation automatically. when the auxiliary winding supplies the vcc pin voltage, the ovp is able to detect an excessive output voltage, such as when the detection circuit for output control is open in the secon dary - side circuit because the vcc pin voltage is proportional to the output voltage. the output voltage of the secondary - side circuit at ovp operation, v out(ovp) , is approximately given as below : out(normal) : output voltage in normal operation v cc(normal) : vcc pin voltage in normal operation 8.16 reg overvoltage protection (reg_ovp) the ic has reg o vervoltage protection (reg_ovp) for the overvoltage of the reg pin . when the reg pin vol tage increases to reg pin ovp threshold voltage, v reg(ovp) = 12.4 v , the reg_ovp is activated and the ic stops switching operation at latched state. releasing the latched state is done by dropping the vcc pin voltage below reg pin overvoltage protection release threshold voltage, v cc ( l.off ) = 5.0 v. 8.17 overcurrent protection (ocp) the overcurrent protection (ocp) detects the drain current, i d , on pulse - by - pulse basis, and limits output power. in figure 8 - 36 , this circuit enables the value of c3 for shunt capacitor to be smaller than the value of ci for current resonant capacitor, and the detection current through c3 is small. thus, the loss of t he detection resistor, r ocp , is reduced, and r ocp is a small - sized one available. t here is no convenient method to calculate the accurate resonan t current value according to the mains input and output conditions , and others . thus, r ocp , c3, and c6 should b e adjusted based on actual operation in the application. the following is a reference adjusting method of r ocp , c3, r6, and c8: c 3 and r ocp c 3 is 100pf to 330pf ( around 1 % of ci value ). r ocp is around 100 . given the current of the high side power mosfet at on state as i d(h) . r ocp is calculated equation ( 14 ) . the detection voltage of r ocp is used the detection of the c apacitive m ode o peration ( see section 8.12 ). therefore, setting of r ocp and c 3 should be taken account of both ocp and the c apacitive m ode o peration. r 6 and c 8 are for high frequency noise reduction. r 6 is 100 to 470 . c 6 is 100 pf to 1000 pf. figure 8 - 36 . rc pin peripheral circuit the ocp operation has two - step threshold voltage as follows: step i, rc pin threshold voltage (low), v rc(l) : this st ep is active first. when the absolute value of the rc pin voltage increases to more than |v oc(l) | = 1.50 v, c6 connected to the css pin is discharged by i css(l) = 1.8 ma. thus, the switching frequency increa ses, and the output power is limited. during discharging c6, when the absolute value of the rc pin voltage decreases to |v rc(l) | or less, the discharge stops. step ii, rc pin threshold voltage (high - speed), v rc(s) : this step is active second. when the absolute value of the rc pin voltage increases to more than |v rc(s) | = 2.30 v, the high - speed ocp is activated, and power mosfets reverse on and off. a t the same tim e, c6 is discharged by i css(s) = 20.5 ma. thus, the switching t 1 p l r 6 c v c i c 3 c 8 v s v g l v g h g n d c s s u 1 1 5 1 1 5 7 8 1 0 1 6 i ( h ) r c c 6 r o c p r 7 r 5 q ( h ) q ( l )
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 23 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 frequency quickly increases, and the output power is quickly limited. this step operates as protections for exceeding overcurrent, such as the output shorted. when the absolute value of the rc pin voltage decreases to |v rc(s) | or less, the operation is changed to the above step i. 8.18 overload protection (olp) figure 8 - 37 shows the overload protection (olp) waveforms . when the absol ute value of rc pin voltage increases to |v rc(l) | = 1.50 v by increasing of output power, the overcurrent protection (ocp) is activated. after that, the c7 c onnected to cl pin is charged by i cl(src) = ? 17 a. when the ocp state continues and cl pin voltage increases to v cl(olp) , the olp is activated. when cl pin voltage becomes the threshold voltage of olp, v cl(olp) = 4. 2 v, the olp is activated and the switching operation stops. during the olp operation, the intermittent operation by uvlo is repeated ( see section 8.15 ). when the fault condition is removed, the ic returns to normal operation automatically. figure 8 - 37 . olp waveform pl pin and cl pin setup: the primary - side winding current as shown in figure 8 - 38 includes the mag netizing current not transferred to the secondary - side circuit, and the load current proportional to the output current. the current separated from the primary - side winding current by c3 flows to the pl pin. as shown in figure 8 - 39 , the primary - side winding current flows to the c7 connected to cl pin during the high side power mosfet turning on. the magnetizing current becomes zero by charging and discharging. only the load current is charged to c7. as a result, the cl pin voltage is proportional to the output current. on actual operation of the application, c7 connected to the cl pin should be adjusted so that ripple voltage of the cl pin reduces. r7 connected to the pl pin should be adjusted so that the olp at the minimum mains input voltage is activated before the ocp limited by the low threshold voltage of ocp, v rc(l) . the pl pin voltage and the cl pin voltage must be within the absolute maximum ratings of ? 0.3 to 6 v, by adjusting r7, in the ocp operation point at the minimum mains input voltage. when the proportional voltage to the output current is unused, the pl pin should be pulled down by the resistance of about 47 k connected between pl pin and gnd pin. figure 8 - 38 . the peripheral circuit of pl pin and cl pin figure 8 - 39 . the waveforms of cl pin 8.19 t hermal shutd o wn (tsd) when the junction temperature of the ic reach to the thermal shutdown temperature t j(tsd) = 140 c (min.), thermal shutd o wn (tsd) is activated and the ic stops switching operation. when the vcc pin voltage is decreased to v cc ( p.off ) = 8.9 v or less and the junction temperature of the ic is decreased to less than t j(tsd) , the ic restarts . during the protection mode, restart and stop are repeated. when the fault condition is remove d, the ic returns to normal operation automatically. v c c p i n v o l t a g e v g h / v g l 0 0 v c c ( p . o f f ) v c c ( o n ) r c p i n v o l t a g e c l p i n v o l t a g e v r c ( l ) v r c ( l ) v c l ( o l p ) 0 0 c h a r g e d b y i c l ( s r c ) t 1 p l r 6 c v c i c 3 c 8 v s v g l v g h g n d u 1 1 5 1 1 7 8 1 0 1 6 r c r o c p r 7 q ( h ) q ( l ) c l 6 c 7 r 4 v s e n c 4 r 2 r 3 c 1 1 m a i n s i n p u t o u t p u t c u r r e n t l o a d c u r r e n t m a g n e t i z i n g c u r r e n t c l p i n v o l t a g e c l p i n s o u r c e c u r r e n t r o c p v o l t a g e v g h p i n v o l t a g e 0 v 0 a 0 v p r o p o r t i o n a l v o l t a g e t o o u t p u t c u r r e n t l o a d c u r r e n t m a g n e t i z i n g c u r r e n t
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 24 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 9. design notes 9.1 external components take care to use the proper rating and proper type of components. 9.1.1 input and o u tput e lectrolytic c apacitor s apply proper derating to a ripple current, a voltage, and a temperature rise. it is required to use the high ripple current and low impedance type e lectrolytic c apacitor that is designed for switch mode power supplies . 9.1.2 resonant t ransformer the resonant power supply uses the leakage inductance of a transformer. ther efore, to reduce the effect of the eddy current and the skin effect, the wire of transformer should be us ed a bundle of fine litz wires. 9.1.3 current d etection r esistor, r ocp to reduce the effect of the high frequency switching current flowing through r ocp , c ho ose the resister of a low internal inductance type. in addition , its allowable dissipation should be chosen suitable . 9.1.4 current r esonant c apacitor, ci since a l arge resonant current flows through ci , ci should be use d a low loss and a high current capability capacitor such as a polypropylene film capacitor. in addition, ci must be taken into account its frequency characteristic because a high frequency current flows. 9.1.5 gate pin peripheral circuit the vgh and vgl pin s are gate drive output s for external power mo sfets. the se peak source and sink current s are C 540 ma and 1.50 a , respectively . to make a turn - off speed faster, connect the diode, d s , as shown in figure 9 - 1 . when r a and d s is adjusted, the following contents should be taken into account: the power losses of power mosfets, gate waveforms (for a ringing reduction caused by a pattern layout, etc.), and emi noises. to prevent the malfunction s caused by steep d v /dt at turn - off of power mosfet s, connect r gs of 10 k to 100 k between the g ate and s ource pins of the power mosfet with a minimal length of pcb traces . when the se gate resistances are adjusted, the gate waveforms should be checked that the dead time is ensur ed as shown in figure 9 - 2 . figure 9 - 1 . power mosfet peripheral circuit figure 9 - 2 . dead time c onfirmation 9.2 pcb trace layout and component placement t he pcb circuit design and the component layout significantly affect a power supply operation, emi noise s , and power dissipation . thus, to reduce the impedance of the high frequency trace s on a pcb (see figure 9 - 3 ), they should be designed as wide t race and small loop as possible . in addition, ground traces should be as wide and short as possible so that radiated emi levels can be reduced. figure 9 - 3 . high frequency current loops (hatched areas) d s r a r g s d r a i n s o u r c e g a t e h i g h - s i d e g a t e l o w - s i d e g a t e v t h ( m i n . ) v t h ( m i n . ) d e a d t i m e d e a d t i m e
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 25 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 figure 9 - 4 shows the circuit design example. t he pcb trace design should be also taken into account as follows: 1) main circuit trace the main trace s that s witching current flows should be designed as wide trace and small loop as possible. 2) control ground trace if the large current flows through a control ground , it may cause v ary ing electric potential of the control ground ; and this may result in the malfunctions of the ic. therefore, connect the control ground as close and short as possible to the gnd pin at a single - point ground (or star ground) that is separated from the power ground . 3) vcc trace t he trace for supplying power to the ic should be as small loop as possible. if c 3 and the ic are distant from each other, a film capacitor c f (about 0.1 f to 1.0 f) should be connected between the vcc and gnd pin s with a minimal length of pcb traces . 4) trace of peripheral components for the ic control these components should be placed close to the ic, and be connected to the corresponding pin of the ic with as short trace as possible. 5) trace of bootstrap circuit components these components should be connected to the ic pin with as short trace as possible . in addition, the loop for these should be as small as possible. 6) secondary s ide rectifier smoothing circuit trace t he trace s of the rectifier smoothing loop s carry the swit ching current . t hus it should be designed as wide trace and small loop as possible. figure 9 - 4 . peripheral circuit trace example around the ic v a c t 1 a d j v s e n v c c f b c s s c l p l r c s b s t v g h v s v b r e g v g l g n d 1 1 5 1 6 1 7 1 8 4 3 2 u 1 s s c 3 s 9 2 1 7 6 5 1 2 1 3 1 4 9 8 1 0 1 1 p c 1 b r 1 c 1 r 2 r 3 r 4 c 4 c f c 5 c 9 r 8 c 6 r 5 c 7 c 8 r o c p r 6 r 7 c 1 0 c 2 r 1 d 1 c 1 1 d 3 r 1 2 c 1 2 d 4 d 5 r 1 0 r 1 1 q ( h ) q ( l ) d 6 r 1 3 r 1 4 c v c i c 3 d 5 3 d 5 4 c 5 2 c y a ( 6 ) m a i n t r a c e o f s e c o n d a r y s i d e s h o u l d b e w i d e a n d s h o r t ( 1 ) m a i n t r a c e s h o u l d b e w i d e a n d s h o r t ( 3 ) l o o p o f v c c a n d c 2 s h o u l d b e s h o r t ( 2 ) g n d t r a c e f o r i c s h o u l d b e c o n n e c t e d a t a s i n g l e p o i n t ( 4 ) p e r i p h e r a l c o m p o n e n t s f o r i c c o n t r o l s h o u l d p l a c e n e a r i c ( 5 ) b o o t s t r a p t r a c e s h o u l d b e s m a l l l o o p c a d j p f c i c v c c q c r a d j 1 r a d j 2 r 1 5 r 1 6
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 26 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 10. pattern layout example the following show the pcb pattern layout example and the schematic of circuit using SSC3S921 . figure 10 - 1 . pcb pattern layout exampl e lp d (1)main trace should be wide and short (6)main trace of secondary side should be wide and short (4)peripheral components for ic control should place d near ic (2)gnd trace for ic should be connected at a single point (3)loop of vcc and c2 should be short (5)boot strap trace should be small loop s1 s 2 s3 s4
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 27 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 figure 10 - 2 . pcb pattern layout exampl e circuit p s a 5 0 1 1 7 _ r e v . 2 . 0 l p 1 0 1 q p 1 0 4 q p 1 0 3 d p 1 0 2 c p 1 0 3 c p 1 0 2 c p 1 0 4 p f c o u t p f c v c c c x 1 0 1 c n 1 f p 1 0 1 t h 1 0 1 l x 1 0 1 r x 1 0 1 r x 1 0 2 r x 1 0 3 l x 1 0 2 c x 1 0 2 c y 1 0 1 c y 1 0 2 c p 1 0 1 d p 1 0 1 r p 1 0 5 c p 1 0 9 c p 1 1 0 q p 1 0 1 r p 1 1 3 b d 1 0 1 v r 1 0 1 d p 1 0 3 r p 1 1 5 r p 1 1 4 r p 1 0 6 r p 1 0 7 r p 1 0 8 r p 1 0 9 r p 1 0 3 r p 1 0 2 c p 1 0 8 c p 1 0 7 r p 1 1 6 c p 1 0 5 m a i n 1 m a i n 2 c x 1 0 3 c t c o m p c s f b 3 2 4 1 o u t g n d z c d v c c 6 7 5 8 r p 1 1 0 c p 1 1 3 r p 1 0 1 c p 1 0 6 r p 1 0 4 c p 1 1 2 c p 1 1 4 r p 1 1 7 s t b y o n / o f f r p 1 1 1 r p 1 1 2 c p 1 1 1 z p 1 0 1 s s c 2 0 1 6 s q p 1 0 2 d b h 2 8 2 3 1 2 ( d b h 3 3 2 5 1 4 ) 6 , 7 , 8 , 9 ( 5 , 6 , 7 , 8 ) 1 , 2 , 3 ( 1 , 2 ) 1 1 ( 1 2 ) 1 2 ( 1 3 , 1 4 ) c p 1 1 5 d m 2 0 2 r m 2 1 3 c m 2 0 1 v s e n c l r c v c c f b a d j c s s p l s b z m 2 0 1 s s c 3 s 9 2 1 r m 2 0 4 r m 2 0 3 c m 2 0 2 r m 2 0 9 c m 2 0 3 c m 2 0 4 c m 2 0 5 r m 2 1 0 r m 2 1 1 d m 2 0 5 r m 2 1 7 s t r e g v g h v s v b v g l g n d r m 2 2 2 r m 2 2 1 c m 2 1 0 c 2 1 2 c m 2 1 1 c m 2 1 6 d m 2 0 3 d m 2 0 4 r m 2 1 8 d m 2 0 6 c m 2 0 9 c m 2 0 6 r m 2 0 8 c m 2 0 8 q m 2 0 3 r m 2 0 7 r m 2 2 0 p c 2 0 1 p c 2 0 2 c y 2 0 3 1 8 1 6 1 5 1 4 1 2 1 1 1 0 1 2 3 4 5 6 7 8 9 t 1 c m 2 1 7 q m 2 0 1 q m 2 0 2 r m 2 0 6 c m 2 1 3 r m 2 1 2 r m 2 1 4 r m 2 1 5 r m 2 1 6 c m 2 1 5 l p d ( 1 , 2 ) ( 3 , 4 ) ( 7 , 8 ) ( 5 , 6 ) c m 2 1 4 r m 2 1 9 d m 2 0 7 d m 2 0 8 d m 2 0 9 p f c o n / o f f c n 6 0 1 r m 3 1 9 c m 3 0 1 c m 3 0 7 r m 3 0 2 r m 3 0 1 r m 3 0 6 r m 3 0 7 r m 3 0 8 r m 3 0 3 c m 3 0 5 p c 2 0 1 z m 3 0 1 c m 3 0 3 r m 3 0 4 q m 3 0 1 p c 2 0 2 d m 3 0 5 r m 3 1 8 r m 3 1 6 r m 3 2 0 p o w e r _ o n c m 3 0 4 1 2 . 8 v o u t c n 6 0 3 q m 3 0 3 r m 3 1 2 r m 3 1 4 r m 3 1 5 c m 3 1 0 r m 3 1 3 r m 3 1 7 r m 3 0 5 r m 3 1 1 q m 3 0 2 d m 3 0 1 d m 3 0 2 c n 6 0 2 c m 3 0 2 c m 3 0 6 r m 3 0 9 r m 3 1 0 r m 3 2 1 1 8 v o u t s 3 s 4 d m 3 0 3 1 1 1 0 1 2 s 1 s 2 p f c o u t m a i n 1 m a i n 2 r m 2 0 1 r m 2 0 2 d m 2 1 0 d m 2 1 1 r m 2 2 3 p f c v c c 8 6 , 7 9 r m 2 2 5 c m 2 0 7 q m 2 0 4 r m 3 2 2 f a u l t s i g n a l _ 2 f a u l t s i g n a l _ 1 j u m p e r r m 2 0 5 r m 2 2 4 d m 3 0 4 d b s 3 3 6 0 ( t b s 4 0 1 6 ) 1 2 , 3 5 4 ( 1 5 , 1 6 ) ( 1 3 ) ( 1 4 ) ( 1 1 ) ( 1 2 ) ( 9 , 1 0 )
SSC3S921 SSC3S921 - dsj rev. 1. 7 sanken electric co., ltd. 28 jan . 17 , 2 01 8 http://www.sanken - ele.co.jp/en/ ? s anken e lectric c o ., l td. 2015 important notes all data, illustrations, graphs , tables and any other information included in this document (the information ) as to sanken s products listed herein (the sanken products) are current as of the date this document is issued . the information is subject to any change without notice due to improv ement of the sanken products , etc. please make sure to confirm with a sanken sales representative that the contents set forth in this document reflect the latest revisions before use. the sanken products are intended for use as components of general purpose electronic equipment or apparatus (such as home appliances, office equipment, telecommunication equipment, measuring equipment, etc.). prior to use of the sanken products, please put your signature, or affix your name and seal, on the specification documents of the sanken products and return them to sanken. when considering use of the sanken products for any applications that require high er reliability (such as transportation equipmen t and its control systems, traffic signal control systems or equipment , disaster/crime alarm systems, various safety devices, etc.), you must contact a sanken sales representative to discuss the suitability of such use and put your signature, or affix your name and seal, on the specification documents of the sanken products and return them to sanken, prior to the use of the sanken products. the sanken products are not intended for use in any applications that require extremely high reliability such as: aero space equipment; nuclear power control systems; and medical equipment or systems, whose failure or malfunction may result in death or serious injury to people, i.e., medical devices in class iii or a higher class as defined by relevant laws of jap an (colle ctively, the specific applications). sanken assumes no liability or responsibility whatsoever for any and all damages and losses that may be suffered by you, users or any third party, resulting from the use of the sanken products in the specific applicat ions or in manner not in compliance with the instructions set forth herein. in the event of using the sanken p roducts by either (i) combining other products or materials or both therewith or (ii) physically, chemically or otherwise processing or treating o r both the same , you must duly consider all possible risks that may result from all such uses in advance and proceed therewith at your own responsibility. although sanken is making efforts to enhance the quality and reliability of its products, it is impos sible to completely avoid the occurrence of any failure or defect or both in semiconductor products at a certain rate. you must take, at your own responsibility , preventative measures including using a sufficient safety design and confirming safety of any equipment or systems in/for which the sanken products are used, upon due consideration of a failure occurrence rate and derating, etc., in order not to cause any human injury or death, fire accident or social harm which may result from any failure or malfu nction of the sanken products. please refer to the relevant specification documents and sanken s official website in relation to derating. no a nti - radioactive ray design ha s been adopted for the sanken p roducts. the c ircuit constant , operation examples, circuit examples, pattern layout examples, design examples , recommended examples , all information and evaluation results based thereon, etc., described in this document are presented for the sole purpose of refe rence of use of the sanken products . sanken assume s no responsibility whatsoever for any and all damages and losses that may be suffered by you, users or any third party, or any possible infringement of any and all property rights including intellectual property rights and any other rights of you, u sers or any third party , result ing from the information . no information in this document can be transcribed or copied or both without sankens prior written consent. regarding the information, no license, express, implied or otherwise, is granted hereby under any intellectual property rights and any other rights of sanken. unless otherwise agreed in writing between sanken and you, sanken makes no warranty of any kind, whether express or implied, including, without limitation, any warranty (i) as to the quality or performance of the sanken products (such as implied warranty of merchantability, and implied warranty of fitness for a particular purpose or special environment), (ii) that any sanken product is delivered free of claims of third parties by way of infringement or the like, (iii) that may arise from course of performance, course of dealing or usage of trade, and (iv) as to the information (including its accuracy, usefulness, and reliability). in the event of using the sanken products, you must use the same after carefully examining all applicable environmental laws and regulations that regulate the inclusion or use or both of any particular controlled substances, including , but not limi ted to , the eu rohs directive , so as to be in strict compliance with such applicable laws and regulations . you must not use the sanken products or the information for the purpose of any military applications or use, including but not limited to the development of weapons of mass destruction. in the event of exporting the sanken products or the information , or providing them for non - residents, you must comply with all applicable export control laws and regulations in each country including the u.s. export administration regulations (ear) and the foreign exchan ge and foreign trade act of japan , and follow the procedures required by such applicable laws and regulations. sanken assumes no responsibility for any troubles, which may occur during the transportation of the sanken products including the falling thereof , out of sankens distribution network. although sanken has prepared this document with its due care to pursue the accuracy thereof, sanken does not warrant that it is error free and sanken assumes no liability whatsoever for any and all damages and losses which may be suffered by you resulting from any possible error s or omissions in connection with the information. please refer to our official website in relation to general instructions and directions for us ing the sanken products, and refer to the releva nt specification documents in relation to particular precautions when using the sanken products. all rights and title in and to any specific trademark or tradename belong to sanken and such original right holder(s). dsgn - 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