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SG6846B -- Highly Integrated Green-Mode PWM Controller
October 2008
SG6846B Highly Integrated Green-Mode PWM Controller
Features
Low Startup Current: 8A Low Operating Current: 3.7mA Peak-Current Mode Operation with Cycle-by-cycle Current Limiting PWM Frequency Continuously Decreasing with Burst Mode at Light Loads VDD Over Voltage Protection (OVP) AC Input Brownout Protection with Hysteresis Constant Output Power Limit (Full AC Input Range) Internal Latch Circuit for OVP, OTP, and OCP (BLSY, BLSZ) Two-level OCP Delay with 200ms Programmable PWM Frequency with Frequency Hopping OCP Threshold is 2/3 Peak Current Limit Soft Startup Time: 5ms
Description
The highly integrated PWM controller, SG6846B, provides several features to enhance the performance of fly-back converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency under light-load conditions. Under zero-load conditions, the power supply enters burst-mode. This completely shuts off PWM output. If VFB is larger than around 1.6V, PWM pulses out. This green-mode function enables power supplies to meet international power conservation requirements. The SG6846B is designed for SMPS with surge-current output. It is incorporated with a two-level OCP function. Besides, the cycle-by-cycle current limiting, if the switching current is higher than OCP threshold and lasts for 200ms, SG6846B stops gate immediately and latches itself (BLSY version) or restarts after VDD charges up to 16.5V (BCSY version). SG6846B also integrates frequency-hopping function internally. The frequency hopping function helps reduce EMI emission of a power supply with minimum line filters. It has builtin synchronized slope compensation, proprietary internal compensation for constant output power limit over universal AC input range. The gate output is clamped at 18V to protect the external MOSFET from over-voltage damage. Protection include: AC input brownout protection with hysteresis and VDD over-voltage protection. For overtemperature protection, an external NTC thermistor can be applied to sense the ambient temperature. When OCP, VDD OVP, or OTP are activated, an internal latch circuit is used to latch-off the controller. The latch resets when VDD supply is removed. SG6846B is available in 8-pin SOP package.
Applications
General-purpose switch-mode power supplies and flyback power converters, including: Power Adapters Open-frame SMPS SMPS with Surge-current Output, such as for Printers, Scanners, Motor Drivers
Ordering Information
Part Number
SG6846BLSY SG6846BLSZ SG6846BCSY SG6846BCSZ
Operating Temperature Range
-40 to +105C -40 to +105C -40 to +105C -40 to +105C
OCP Latch
Yes Yes No No
Eco Status
Green RoHS Green RoHS
Package
8-Pin Small Outline Package (SOP) 8-Pin Small Outline Package (SOP) 8-Pin Small Outline Package (SOP) 8-Pin Small Outline Package (SOP)
Packing Method
Tape & Reel Tape & Reel Tape & Reel Tape & Reel
For Fairchild's definition of "green" Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html.
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3 www.fairchildsemi.com
SG6846B -- Highly Integrated Green-Mode PWM Controller
Typical Application
L
AC input
EMI Filter
+ +
VO+
N VO+ 7 3 +
VIN RI FB
VDD
GATE 8 SENSE 6
4
2
GND
1
RT 5
SG6846B
Figure 1. Typical Application
Block Diagram
4 0.9V/0.7V
VDD
VIN
3 Over Power Compersation 0.895-0.065 XVIN
Soft Driver
8
GATE
VDD -TH-G VDD 7
UVLO Internal BIAS
Q
S R
OSC
Green Mode
6.2V
3R
2
+ 16.5V/10.5V 1R
FB
Latch
Slope Compensation Blanking Circuit 2R SCP Delay OTP Delay OCP Delay 1.15V
1R
6
SENSE
23.6V
Debounce
IRT
RT 5
1.05V
1 GND
Figure 2. Block Diagram
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3 www.fairchildsemi.com 2
SG6846B -- Highly Integrated Green-Mode PWM Controller
Marking Information
SG6846BFTP
XXXXXXXXYWWV
F: L = OCP Latch, C = OCP auto-recovery T: S = SOP P: Z = Lead Free + ROHS Compatible Null = regular package XXXXXXXX: Wafer Lot Y: Year; WW: Week V: Assembly Location
Marking for SG6846BLSZ (Pb-free) SG6846BCSZ (Pb-free)
Figure 3. Top Mark 1
: Fairchild logo Z: Plant Code X: Year Code Y: Week Code TT: Die Run Code F: L = OCP Latch, C = OCP auto-recovery T: Package type, S = SOP P: Y = Green Package M: Manufacturing flow code Marking for SG6846BLSY (Green-compound) SG6846BCSY (Green-compound) Figure 4. Top Mark 2
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Pin Configuration
Figure 5. Pin Configuration
Pin Definitions
Pin #
1 2
Name
GND FB
Function
Ground Feedback Line-voltage Detection Reference Setting Temperature Detection
Description
Ground. The signal from the external compensation circuit is fed into this pin. The PWM duty cycle is determined in response to the signal from this pin and the currentsense signal from pin 6. Line-voltage detection is used for brownout protection with hysteresis. Constant output power limit over universal AC input range is achieved using this pin. Add a low-pass filter to filter out line ripple on the bulk capacitor. A resistor from the RI pin to ground generates a reference current source that determines the switching frequency. Increasing the resistance reduces the switching frequency. A 26k resistor results in a 65kHz switching frequency. For over-temperature protection, an external NTC thermistor is connected from this pin to the GND pin. The impedance of the NTC decreases at high temperatures. Once the voltage of the RT pin drops below a threshold, PWM output is disabled. The sensed voltage is used for peak-current-mode control and cycle-by-cycle current limiting. If the switching current is higher than OCP threshold and lasts for 200ms, SG6846B turns off immediately. This two-level OCP feature is especially suitable for SMPS with surge current output. If an open-circuit failure occurs in the feedback loop, the internal protection circuit disables PWM output as long as VDD exceeds a threshold. The totem-pole output driver for the power MOSFET; internally clamped below 18V.
3
VIN
4
RI
5
RT
6
SENSE
Current Sense
7 8
VDD GATE
Power Supply Driver Output
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. All voltage values, except differential voltages, are given with respect to GND pin.
Symbol
VDD VL PD JC TJ TSTG TL ESD Supply Voltage
Parameter
Input Voltage to FB, SENSE, VIN, RT, RI Pins Power Dissipation at TA<50C Thermal Resistance (Junction-to-Case) Operating Junction Temperature Storage Temperature Range Lead Temperature, Wave Soldering, 10 Seconds Human Body Model, JESD22-A114 Charge Device Model, JESD22-C101 SOP SOP
Min.
-0.3
Max.
30 7.0 400 54.4
Unit
V V mW C/W C C C kV
-40 -65
+150 +150 +260 5.0 1.5
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings.
Symbol
TA
Parameter
Operating Ambient Temperature
Min.
-40
Max.
+105
Unit
C
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Electrical Characteristics
VDD = 15V and TA = 25C unless otherwise noted.
Symbol VDD Section
VDD-OP VDD-ON VDD-OFF VDD-SCP VDD-LH IDD-ST IDD-OP VDD-OVP tD-VDDOVP IDD-OVP
Parameter
Test Condition
Min.
Typ.
Max.
Unit
Continuously Operating Voltage Turn-on Threshold Voltage Turn-off Voltage Threshold Voltage on VDD for Short-Circuit Protection Threshold Voltage for Latch-off Release Startup Current Operating Supply Current VDD Over-Voltage Protection (Latch off) VDD OVP Debounce Time VDD OVP Latch-off Holding Current RI = 26k VDD = 5V 30 VDD-ON - 0.16V GATE Open 23 15.5 9.5 16.5 10.5
20 17.5 11.5
V V V V V A mA V s
VDD-OFF VDD-OFF VDD-OFF +0.5V +1.0V +1.5V 3 4 8 3.7 24 150 50 70 5 30 5.0 25
A
VIN Section
VIN-OFF VIN-ON PWM Turn-off Threshold Voltage PWM Turn-on Threshold Voltage 0.65 VIN-OFF +0.18 0.70 VIN-OFF +0.20 0.75 VIN-OFF +0.22 V V
Feedback Input Section
AV ZFB VFBO Input-Voltage to Current-Sense Attenuation Input Impedance FB Pin Open Voltage 1/3.5 4.0 5.2 1/4.0 5.5 6.2 1/4.5 7.0 6.6 V/V k V
Current Sense Section
ZSENSE tPD tLEB VSLOPE VSTH1V VSTH3V VSTH1V-2/3 VSTH3V-2/3 tD-OCP tD-Short tSS-65KHz tSS-130KHz Input Impedance Delay to Output Leading-edge Blanking Time Slope Compensation Threshold Voltage for Current Limit Threshold Voltage for Current Limit OCP Threshold Voltage for Current Limit OCP Threshold Voltage for Current Limit Delay Time for Over-Current Protection Output Short Circuit Protection delay time Period During Soft Start Time Duty = DCYMAX VIN = 1V VIN = 3V VIN = 1V VIN = 3V RI = 26k VCS > VSTH, RI = 26k, VDD < VDD-SCP RI = 26k RI = 13k 270 0.30 0.80 0.67 0.58 0.48 175 6 4.5 2.25 12 100 360 0.33 0.83 0.70 0.61 0.51 200 7 5.0 2.50 0.36 0.86 0.73 0.64 0.54 225 8 5.5 2.75 250 k ns ns V V V V V ms ms ms ms
Continued on following page...
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
( 1 ) normal operation
(4 ) VDD < 12 V ? NO
YES
NO
(2 ) IP > 2 / 3 IPK ?
(5 ) Timing = 200ms
YES
NO (6 ) VDD < = 12 V ?
SCP
(3 ) Timing = 8 ms
OCP
(7 ) Gate-off
SCP
Figure 6. SG6846B OCP/SCP Logic Flow Diagram
Electrical Characteristics (Continued)
VDD = 15V and TA = 25C unless otherwise noted.
Symbol Oscillator Section
fOSC
Parameter
Test Condition
Min.
Typ.
Max.
Unit
Normal PWM Frequency
Center Frequency Jitter Range
RI = 26k, VFB>VN
62 3.7
65 4.2 130 8.4 47.0 2.90 4.4 11.5 22.5 85
68 4.7 136 9.4 49.2 3.26 4.9 12.8 25.0
kHz
fOSC,MAX
Maximum PWM Frequency
Center Frequency Jitter Range
RI = 13k, VFB>VN
124 7.4
kHz
fOSC,MIN thop-1 thop-3 fOSC-G SG VFB-N
Center Minimum PWM Frequency Frequency Jitter Range Jitter Period Jitter period Green-Mode Minimum Frequency Slope for Green-Mode Modulation Pin, FB voltage FB Pin Frequency Reduction Threshold Jitter Range FB Voltage at fOSC-G Pin, FB voltage Jitter Range
RI = 36k, VFB>VN RI = 26k, VFB VN RI = 26k, VFB = VG RI = 26k RI = 26k RI = 26k, VFB = VN
44.8 2.54 3.9 10.2 18.0
kHz ms ms kHz Hz/mV
1.9 3.7 1.4 1.27
2.1 4.2 1.6 1.45
2.3 4.7 1.8 1.62 5
V KHz V KHz % %
VFB-G fDV fDT
RI = 26k, VFB = VG VDD = 11.5V to 20V TA = -30 to 85C
Frequency Variation vs. VDD Deviation Frequency Variation vs. Temperature Deviation
1.5
5.0
Continued on following page...
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Figure 7. PWM Frequency
Electrical Characteristics (Continued)
VDD = 15V and TA = 25C unless otherwise noted.
Symbol PWM Output Section
DCYMAX VOL VOH tR tF VCLAMP
Parameter
Test Condition
Min.
Typ.
Max.
Unit
Maximum Duty Cycle Output Voltage Low Output Voltage High Rising Time Falling Time Gate Output Clamping Voltage
(1)
80 VDD = 15V, IO = 50mA VDD = 12V, IO = 50mA GATE = 1nF GATE = 1nF VDD = 20V 8
85
90 1.5
% V V
350 50 18
ns ns V
Over-Temperature Protection (OTP) Section
IRT VRTTH tDOTP-LATCH RRT-OFF Output Current of RT Pin Threshold Voltage for OTP
RI = 26k
64 1.00
70 1.05 100
76 1.10
A V ms
Over-Temperature Latch-off Debounce Equivalent Impedance of RT for OTP
(1)
RI = 26k RI = 26k 14
15
16
k
RI Section
RINOR RIMAX RIMIN RI Operating Range Maximum RI Value for Protection Minimum RI Value for Protection 13 10 6 36 k M k (1)
Note: 1. The relationship between RRT-OFF and RI is: RRT -OFF = VOTP-LATCH-OFF / IRT = VRT / (70 A x 26 / RI (K ))
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Typical Performance Characteristics
Turn-on Threshold Voltage (V DD-ON ) vs Temperature
1 7 .0 1 1 .5 1 1 .0
Turn-off Voltage (V DD-OFF) vs Temperature
1 6 .8
V DD-ON (V)
V DD-OFF (V)
-4 0 -2 5 -1 0 5 20 35 50 65 80 95 110 125
1 6 .6
1 0 .5 1 0 .0 9 .5 9 .0 -4 0 -2 5 -1 0 5 20 35 50 65 80 95 110 125
1 6 .4 1 6 .2
1 6 .0
Temperature ( )
Temperature ( )
Figure 8. Turn-on Threshold Voltage (VDD-ON) vs. Temperature
Figure 9. Turn-off Threshold Voltage (VDD-OFF) vs. Temperature
Startup Current (I
26. 0 22. 0 18. 0 14. 0 10. 0 6. 0 -40 -25 -10 5 20 35
DD -ST
) vs Temperature
6 .0
Operating Supply Current (IDD-op) vs Temperature
5 .5
IDD-op (mA)
50 65 80 95 110 125
IDD-ST (A)
5 .0
4 .5
4 .0
Temperature ()
-4 0
-2 5
-1 0
5
20
35
50
65
80
95
110
125
Temperature ( )
Figure 10. Startup Current (IDD-ST) vs. Temperature
Figure 11. Operating Supply Current (IDD-op) vs. Temperature
0. 66
OCP Threshold Voltage for Current Limit (VSTH1V-2/3) vs Temperature
0. 60 0. 58
OCP ThresholdVoltage for Current Limit (VSTH3V-2/3) vs Temperature
0. 64 0. 62
VSTH1V-2/3 (V)
0. 60
VSTH3V-2/3 (V)
-40 -25 -10 5 20 35 50 65 80 95 110 125
0. 56 0. 54 0. 52 0. 50 -40 -25 -10 5 20 35 50 65 80 95 110 125
0. 58 0. 56
Temperature ( )
Temperature ()
Figure 12. OCP Threshold Voltage for Current Limit (VSTH1V-2/3) vs. Temperature
Figure 13. OCP Threshold Voltage for Current Limit (VSTH3V-2/3) vs. Temperature
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Typical Performance Characteristics (Continued)
Normal PWM Frequency (f OSC ) vs Temperature
64. 0
Maximum Duty Cycle (DCYmax) vs Temperature
8 7.2
8 7.0
63. 5
DCYmax (%)
-40 -25 -10 5 20 35 50 65 80 95 110 125
f OSC (kHz)
8 6.8
63. 0
8 6.6 8 6.4
62. 5
62. 0
8 6.2 -4 0 -2 5 -10 5 20 35 50 65 80 95 110 12 5
Temperature ( )
Temperature ( )
Figure 14. Normal PWM Frequency (fOSC) vs. Temperature
Figure 15. Maximum Duty Cycle (DCYmax) vs. Temperature
Output Current of RT Pin (IR T ) vs Temperature
70. 8
1. 10
Trigger Voltage of OTP (V TT H ) vs Temperature R
70. 6 70. 4
1. 08
70. 2 70. 0
VRTTH (V)
-40 -25 -10 5 20 35 50 65 80 95 110 125
IR T (A)
1. 06
1. 04
1. 02
69. 8
1. 00 -40 -25 -10 5 20 35 50 65 80 95 110 125
Temperature ()
Temperature ()
Figure 16. Output Current of RT pin (IRT) vs. Temperature
Figure 17. Trigger Voltage of OTP(VRTTH) vs. Temperature
PW M Turn-on Threshold Voltage (V IN-ON ) vs Temperature
0.925
0 .7 1 5 0 .7 1 0
PW M Turn-off Threshold Voltage (V IN-OFF ) vs Temperature
0.920
V IN-ON (V)
V IN-OFF (V)
-40 -25 -10 5 20 35 50 65 80 95 1 10 125
0 .7 0 5 0 .7 0 0 0 .6 9 5
0.915
0.910
0.905
0 .6 9 0 -4 0 -2 5 -1 0 5 20 35 50 65 80 95 110 125
Temperature ( )
Temperature ( )
Figure 18. PWM Turn-on Threshold Voltage (VIN-ON) vs. Temperature
Figure 19. PWM Turn-off Threshold Voltage (VIN-OFF) vs. Temperature
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Operation Description
Startup Operation
The turn-on/turn-off thresholds are fixed internally at 16.5V and 10.5V. To enable the SG6846B during startup, the hold-up capacitor must first be charged to 16.5V through the startup resistor. If an open-circuit or short-circuit to ground occurs at the RI pin, the internal protection circuit immediately shuts down the controller. The hold-up capacitor continues to supply VDD before energy can be delivered from the auxiliary winding of the main transformer. The VDD must not drop below 10.5V during this startup process. This UVLO hysteresis window ensures that the hold-up capacitor can adequately supply VDD during startup. The typical startup current is only 8A, which allows a high-resistance, low-wattage startup resistor to be used. For constant output power limit over a universal inputvoltage range, the peak-current threshold is adjusted by the voltage of the VIN pin. Since the VIN pin is connected to the rectified AC input line voltage through the resistive divider, a higher line voltage generates a higher VIN voltage. The threshold voltage decreases as the VIN increases, making the maximum output power at high line input voltage equal to that at low line input. The value of R-C network should not be so large it affects the power limit (shown in Figure 20). R and C should put on less than 300 and 1000pF, respectively, to minimize power loss. A 1.5M/0.25W startup resistor and a 10F/25V VDD hold-up capacitor are sufficient for a universal input range. The required operating current has been reduced to 3.7mA, which enables higher efficiency and reduces the VDD hold-up capacitance requirement.
fPWM(kHz) =
1690 R I (k )
(2)
If an open-circuit or short-circuit to ground occurs at the RI pin, the internal protection circuit immediately shuts down the controller.
Two-level Over-current Protection (OCP)
The cycle-by-cycle current limiting shuts down the PWM immediately when the switching current is over the peak-current threshold. Additionally, when the switching current is higher than over-current threshold, the internal counter counts down. When the total accumulated counting time is more than ~200ms (RI = 26k), the controller is latched off and the internal counter counts up. When the switching current is lower than overcurrent threshold, the internal counter counts down. When the total accumulated counting time is more than ~200ms (RI = 26k), the controller is latched off. This two-level OCP protection and up/down counter are especially designed for SMPS with surge current output, such as those for printers, scanners, and motor drivers.
Constant Output Power Limit
For constant output power limit over universal inputvoltage range, the peak-current threshold is adjusted by the voltage of the VIN pin. Since the VIN pin is connected to the rectified AC input line voltage through the resistive divider, a higher line voltage generates a higher VIN voltage. The threshold voltage decreases as VIN increases, making the maximum output power at high-line input voltage equal to that at low-line input.
Brownout Protection
Since the VIN pin is connected through a resistive divider to the rectified AC input line voltage, it can also be used for brownout protection. If the VIN voltage is less than 0.7V, the PWM output is shut off. If the VIN is over 0.9V, the PWM output is turned on again. The hysteresis window for on/off is ~0.2V.
Green-Mode Operation
The proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency under light-load conditions. Maximum on-time is limited to provide protection against abnormal conditions. To further reduce power consumption under zero-load condition, the PWM oscillator is completely turned off and the power supply enters burst-mode. Green mode dramatically reduces power consumption under light-load and zero-load conditions. Power supplies using SG6846B can meet restrictive international regulations regarding standby power consumption.
VDD Over-voltage Protection (OVP)
VDD over-voltage protection is built in to prevent damage. If VDD is over 24V, SG6846B is latched off.
Over-Temperature Protection (OTP)
An external NTC thermistor can be connected from the RT pin to GND. The impedance of the NTC decreases at high temperatures. When the voltage of the RT pin drops below 1.05V, the SG6846B is turned off. For protection-mode options, see Ordering Information.
Oscillator Operation
A resistor connected from the RI pin to GND generates a internal reference current source used to determine the PWM frequency. Increasing the resistance decreases the amplitude of the current source and reduces the PWM frequency. Using a 26k resistor results in a corresponding 65kHz switching frequency. The relationship between RI and the switching frequency is:
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Operation Description (Continued)
Noise Immunity
Noise from the current sense or the control signal may cause significant pulse-width jitter, particularly in continuous-conduction mode. Slope compensation helps alleviate this problem. Good placement and layout practices should be followed. Avoid long PCB traces and component leads. Compensation and filter components should be located near the SG6846B.
Figure 20. Current Sense R-C Filter
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Reference Circuit
P1 F1 RT1
t 2 2 4 3 1
CY1
CX1LF2
BD1
1 2 5
R16 D4 TX1
13 3 6 + 1 2 2
VZ1 P2 P7
1 3 4 2
2
LF1 CY2
R8
3 1
C2
R12 C4 D2
1 2
C16 +
1
+
C12
2
CX2
4
P32V P32V L1
+
32V C13
32V
10 1 7 1 3 9
R1
R2 R3
2
R9 D1
1 + 21 2 +
C11
R17 P16V P16V L2
2 2
11 1 2 3
L4
D3
12 2
1 +
C17 + D5
1
C14
2 1
R4
1
C3
C5
1
R11
+
16V 16V C15
U1
1 GND FB VIN RI GATE VDD SENSE RT 8 7 6 5
2
R13 R6 R10 NTC1 C6
Q1
1 2
FB
2
2 3
L3 R14
P16V
C1
1
+
R5
4
R7
1
3
P16V R15
4 1
FB
FB
P16V
1 P32V
C7
3
C9 U2
2 K R
P16V R18 R19 R21
P32V R20
U3
A
Figure 21. Application Circuit for 32V / 16V Output
BOM
Part No.
R1, R2, R3, R4 R8, R9 R5 R15 R13 R18 R21 R7 R6 R19 R14 R16, R17 R11 R12 R20 R22
Value
470K +/-5% S1M +/-1% 16K2 +/-1% 1K5 +/-5% 10 +/-5% 4K7 +/-5% 15K +/-1% 27K +/-5% 330 +/-1% 102K +/-1% 022 +/-5% 1W 20 +/-5% 20K +/-5% 100K +/-5% 887K +/-1% 10K +/-1%
Part No.
C4 C10,C11 C6,C7 C9 C14,C17 C15 C13,C16 C2 C1 C3 CX1 C8 C5 CX2 D1 D2
Value
103P 630V 102P 1KV 102P 50V 222P 50V 470 25V 220 25V 220 50V 150 400V 4.7 50V 10 50V X1 0.47 275V Y2 222P 250V 100 50V X2 0.1F 275V 1N4148 BYV95C
Part No.
D3 BD1 D4 D5 F1 L1,L2 L4 U3 U1 U2 Q1 TX1 RT1 VZ1
Value
FR103 1.0A 200V DBL406G BYT28-300 BYV32-150 250V4A QUICK 1.8H 10H TL431 +/-1% SG 6846 PC817 7NB60 EI-33 SCK053 14 470V
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
Physical Dimensions
5.00 4.80 3.81
8 5
A
0.65
B
6.20 5.80
4.00 3.80
1 4
1.75
5.60
PIN ONE INDICATOR
(0.33)
1.27
0.25
M
CBA
1.27
LAND PATTERN RECOMMENDATION
0.25 0.10 1.75 MAX
C 0.10 0.51 0.33 0.50 x 45 0.25 C
SEE DETAIL A
0.25 0.19
OPTION A - BEVEL EDGE
R0.10 R0.10
GAGE PLANE
0.36
OPTION B - NO BEVEL EDGE
NOTES: UNLESS OTHERWISE SPECIFIED A) THIS PACKAGE CONFORMS TO JEDEC MS-012, VARIATION AA, ISSUE C, B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS DO NOT INCLUDE MOLD FLASH OR BURRS. D) LANDPATTERN STANDARD: SOIC127P600X175-8M. E) DRAWING FILENAME: M08AREV13
8 0 0.90 0.406
SEATING PLANE
(1.04)
DETAIL A
SCALE: 2:1
Figure 22. 8-Pin Small Outline Package (SOP)
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild's worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor's online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/.
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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SG6846B -- Highly Integrated Green-Mode PWM Controller
(c) 2008 Fairchild Semiconductor Corporation SG6846B * Rev. 1.3.3
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