ts 19 1 6 1.7a boost wled driver 1 / 10 version: a14 so t - 26 general description the ts1916 is a step - up (boost) converter designed for driving up to 10 series white leds for backlighting application . the ts1916 uses current mode, 1mh z fixed frequency architecture to regulate the led current, whi ch is set through an external current sense resistor. it s low f eedback voltage reduces power loss and improves efficiency. the ov p pin monitors the output voltage and turns off the converter if an over - voltage condition is present due to an open circuit c ondition. the ts1916 includes under - voltage lockout, current limiting and thermal shutdown protection preventing damage in t he event of an output overload. features 2.5 v to 5.5 v operating input voltage range drives up to 10 series w hite leds 1m hz f ixed s w itching f requency wide range for pwm dimming (200hz to 200 k hz) i nternal 1.7a switching current limit over voltage p rotection (ovp) internal soft - start f unction c urrent limit and t hermal shutdown protection under voltage l ockout application digital still ca meras portable electronics pda s and palm - top computers local boost regulator ordering information part no. package packing ts191 6cx6 rf g so t - 26 3 k pcs / 7 reel note: g denotes for halogen - and antimony - free as those which contain <900ppm bromine, <90 0ppm chlorine (<1500ppm total br + cl) and <1000ppm antimony compounds absolute maximum ratings parameter symbol limit unit v cc pin voltage v cc - 0.3 to 6 v sw pin voltage v sw - 0.3 to 45 v ov p pin voltage v ov p - 0.3 to 45 v en, f b pin voltage - 0.3 to 6 v power dissipation p d ( t j - t a ) / r ja mw storage temperature range t st g - 65 to +150 c operating junction temperature range t op - 40 to + 125 c thermal resistance from j unction to case r jc 15 c/w thermal resistance from j unction to ambient r ja 40 c/w note: r ja is measured with the pcb copper area of approximately 1 in 2 (multi - layer). pin definition : 1. switch 2. ground 3. feedback 4. enable 5. ovp 6. v cc
ts 19 1 6 1.7a boost wled driver 2 / 10 version: a14 electrical specifications ( t a = 25 o c , v in =5v, i out = 2 0 m a unless otherwise noted ) characteristics symbol conditions min typ max units input voltage range v cc 2.5 - - 5.5 v step - up voltage range v out 3 - - 40 v ov p sense voltage v ov p -- 38 -- v under voltage lockout u vlo rising - - 2.2 2.4 v uvlo hysteresis - - 100 - - mv feedback voltage v fb 190 200 210 mv en threshold logic - high voltage v ih 2.0 - - - - v lo gic - low voltage v il - - - - 0.4 v en hysteresis - - 200 - - mv operating quiescent current i ccq i out = 0ma, v fb =0.5v - - 300 500 a sd v en =0v, t en > 20ms - - 1 10 a (note ) i lim duty=50% - - 1.7 - - a mosfet on - resistance (note ) r ds(on) - - 0.6 1.0 max - - 88 - - % line regulation v cc = 3v to 5v - - 1 - - % swit ching frequency f osc 0.75 1 1.25 mhz dimming clock rate f dim 0.2 - - 200 k hz fb input leakage current i fb - lkg v fb = 0.5v - - 0.01 100 na sw leakage current i swl v lx = 30v, v fb =0.5v - - - - 1 a en input leakage current i en - lkg1 v en = v cc - - 1.5 3 a e n - lkg2 v en = gnd - - - - 1 a shdn - - 10 - - m s thermal shutdown t sd - - 160 - - c thermal shutdown hysteresis t sh - - 30 - - note: g uaranteed by design
ts 19 1 6 1.7a boost wled driver 3 / 10 version: a14 block diagram pin description pin number pin name description 1 sw switch o utput p in 2 gnd ground pin 3 fb feedback p in ; put a resistor to gnd to setting the current 4 en enable with dimming pin; internal pull - low; logic high active 5 ov p ovp sense pin 6 v cc power i nput p in v c c s w c o n t r o l a n d d r i v e r l o g i c e n r e f e r e n c e 1 . 2 3 8 v s o f t s t a r t c u r r e n t s e n s e s l o p e c o m p e n s a t i o n o s c i l l a t o r 1 m h z f b e r r o r a m p l i f i e r s u m m i n g c o m p a r a t o r t h e r m a l s h u t d o w n e n a b l e l o g i c g n d n - m o s 1 0 m s 3 0 0 m v s h u t d o w n o v p o v u v l o
ts 19 1 6 1.7a boost wled driver 4 / 10 version: a14 application circuit for 10 series led a pplicatio n with dimming i led =v fb /r3 , v fb =200mv
ts 19 1 6 1.7a boost wled driver 5 / 10 version: a14 application information setting the iled current application circuit item shows the basic application circuit with ts1916 adjustable outpu t version. the external resistor sets the led output current according to the following equation: i led = ( v fb / r 3 ) part no. i led r3 ts1916 20ma 10 0.571 over voltage protection the over voltage protection is detected by a junctio n breakdown detecting circuit. once v out goes over the detecting voltage, sw pin stops switching and the power n - mosfet will be turned off. then, the v out will be clamped to be near v ovp . under voltage lockout (uvlo) to avoid mis - operation of the device a t low input voltages an under voltage lockout is included that disables the device, if the input voltage falls below (2.25v - 100mv). input capacitor selection the input capacitor reduces the surge current drawn from the input and switching noise from the d evice. the input capacitor impedance at the switching frequency shall be less than input source impedance to prevent high frequency switching current passing to the input. a low esr input capacitor sized for maximum rms current must be used. ceramic capaci tors with x5r or x7r dielectrics are highly recommended because of their low esr and small temperature coefficients. a 4.7f ceramic capacitor for most applications is sufficient. for a lower output power requirement application, this value can be decrease d. output capacitor selection the output capacitor is required to keep the output voltage ripple small and to ensure regulation loop stability. the output capacitor must have low impedance at the switching frequency. ceramic capacitors with x5r or x7r die lectrics are recommended due to their low esr and high ripple current. a 1 f ceramic capacitors works for most of the applications. higher capacitor values can be used to improve the load transient response.
ts 19 1 6 1.7a boost wled driver 6 / 10 version: a14 electrical characteristics curve figure 1 . power on from v in figure 2 . power on from en figure 3 . steady state operation figure 4 . normal operation i nto ovp figure 5. pwm dimming f rom en (200hz) v in =5v, 4wleds, i out =150ma figure 6. pwm dimming f rom en (2 0hz) v in =5v, 4wleds, i out =150ma
ts 19 1 6 1.7a boost wled driver 7 / 10 version: a14 electrical characteristics curve figure 7 . reference voltage vs. input voltage figure 8. reference voltage vs. temperature figure 9. quiescent current vs. input voltage figure 10. output voltage vs. output current figure 11. led current vs. duty figure 12. frequency vs. temperature
ts 19 1 6 1.7a boost wled driver 8 / 10 version: a14 electrical characteristics curve figure 13. frequency vs. input voltage figure 14. enable voltage vs. input voltage figure 15. efficiency vs. output current figure 16. efficiency vs. input voltage
ts 19 1 6 1.7a boost wled driver 9 / 10 version: a14 sot - 26 mechanical drawing unit: millimeters marking diagram jc = device code y = year code ( 4 =2014 , 5 =2015 , 6 =2016 , 7 =2017 , 8 =2018 , 9 =2019 ) w = week: 01~26 (a~z) 27~52 (a~z) x = internal code
ts 19 1 6 1.7a boost wled driver 10 / 10 version: a14 notice spec ifications of the products displayed herein are subject to change without notice. tsc or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. information contained herein is intended to provide a product description only. no license, express or implied, to any intellectual property rights is granted by this document. except as provided in tscs terms and conditions of sale for such products, tsc assumes no liability whatsoever, and disclaims any express or implied wa rranty, relating to sale and/or use of tsc products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right. the products shown herein are not designed for use in medical, life - saving, or life - sustaining applications. customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify tsc for any damages resulting from such improper use or sale.
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