SG6902 Fairchild Semiconductor, SG6902 Datasheet
SG6902
Related parts for SG6902
SG6902 Summary of contents
Page 1
... PFC loop, in which the overshoot and undershoot of the PFC voltage are clamped. If the feedback loop is broken, the SG6902 shuts off PFC to prevent extra-high voltage on output. Programmable two-level output voltage control reduces the PFC output voltage at low line input to increase the efficiency of the power supply ...
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... XXXXXXXXYWWV ORDERING INFORMATION Part Number Pb-Free SG6902SZ © System General Corp. Version 1.3.1 (IAO33.0022.B3) PIN CONFIGURATION T: S=SOP P : Z=Lead Free + ROHS Compatible Null=regular package XXXXXXXX: Wafer Lot Y: Year; WW: Week V: Assembly Location Package 20-pin SOP - 2 - Product Specification SG6902 www.sg.com.tw • www.fairchildsemi.com September, 2007 ...
Page 3
... The impedance of the NTC thermistor decreases whenever the temperature increases. Once the voltage of the OTP pin drops below the OTP threshold, the SG6902 is disabled. This is the output of the PFC current error amplifier. The signal from this pin is compared with an internal sawtooth and determines the pulse width for PFC gate drive ...
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... Green-Mode PFC / Flyback-PWM Controller www.DataSheet4U.com BLOCK DIAGRAM © System General Corp. Version 1.3.1 (IAO33.0022.B3) Product Specification - 4 - www.sg.com.tw • www.fairchildsemi.com SG6902 September, 2007 ...
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... DD-TH-G Green-off Mode © System General Corp. Version 1.3.1 (IAO33.0022.B3) < 50°C A Test Conditions V –0.16V TH-ON OPFC, OPWM Open, R =24kΩ I OVP R =24kΩ Product Specification SG6902 Value Unit -0.3 to +25.0 V -0.3 to +7.0 V SOP 1.15 W -40 to +125 °C -55 to +150 °C SOP 23.64 °C/W 260 ° ...
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... PWM Frequency OSC F Minimum Frequency in Green Mode OSC-MINFREQ RI RI Pin Resistance Range RI Pin Open Protection RI OPEN If RI> SG6902 Turns Off open RI Pin Short Protection RI SHORT If RI< SG6902 Turns Off short VRMS for UVP and RANGE Symbol Parameter RMS AC Voltage Under-Voltage Protection Threshold ...
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... DD= R =24kΩ 15V; I =100mA DD 13V; I =100mA DD 15V; C 5nF; OPFC= 15V; C 5nF; OPFC= Product Specification SG6902 Min. Typ. Max. Unit 1.5 MHz 70 dB 3 µ 0.25 mA Min. Typ. Max. Unit 90 100 110 µ ...
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... Added to Current Sense Test Conditions V 20V DD= V 15V; I =100mA DD 13V; I =100mA DD 15V; C 5nF; OPWM= 15V; C 5nF; OPWM= www.sg.com.tw • www.fairchildsemi.com Product Specification SG6902 Min. Typ. Max. Unit 2.5 3.1 3.5 V KΩ 0.8 1.2 1.5 mA 4.2 4.5 4 +0. ...
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... System General Corp. Version 1.3.1 (IAO33.0022.B3) Test Conditions Min. R =24kΩ 1.15 1.35 R =24kΩ Test Conditions Min. R =24kΩ www.sg.com.tw • www.fairchildsemi.com Product Specification SG6902 Typ. Max. Unit 100 11 µA 1.20 1.25 V 1.40 1. µs Typ. Max. Unit 50 56 µA 470 Ω ...
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... Product Specification SG6902 Min. Operation Voltge ( Temperature DD-MIN 5℃ 20℃ 35℃ 50℃ 65℃ 80℃ 95℃ 110℃ 125℃ Temperature (℃) Frequency vs. FB Voltage 1.6 1.7 1.8 1.9 2 2.1 2.2 2.3 2.4 2.5 FB Voltage (V) Duty cycle vs. FB Voltage 1 ...
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... Product Specification SG6902 ) vs Temperature RMS-H 5℃ 20℃ 35℃ 50℃ 65℃ 80℃ 95℃ 110℃ 125℃ Temperature (℃ Temperature RMS-L 5℃ 20℃ 35℃ 50℃ 65℃ 80℃ ...
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... Product Specification SG6902 Maximum Duty Cycle ( Temperature MAX 5℃ 20℃ 35℃ 50℃ 65℃ 80℃ 95℃ 110℃ 125℃ Temperature (℃ Temperature OPEN-LOOP 5℃ 20℃ ...
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... Product Specification SG6902 Fall Time ( Temperature F-PWM 5℃ 20℃ 35℃ 50℃ 65℃ 80℃ 95℃ 110℃ 125℃ Temperature (℃) Maximum Duty Cycle ( Temperature MAXPWM 5℃ 20℃ 35℃ ...
Page 14
... PFC loop, in which the overshoot and undershoot of the PFC voltage are clamped. If the feedback loop is broken, the SG6902 shuts off PFC to prevent extra-high voltage on output. Programmable two-level output voltage control reduces the PFC output voltage at low line input to increase the efficiency of the power supply ...
Page 15
... PFC and flyback as a second stage, the output voltage of PFC is usually designed around 250V at low line and 390V at high line. This is to improve efficiency at low-line input. In SG6902, the RANGE pin (open-drain structure) is used for the two-level output voltage setting. ...
Page 16
... Figure 5 shows the total control loop for the average-current-mode control circuit of SG6902. The current source output from the switching charge multiplier-divider can be expressed as: × ...
Page 17
... I S_peak FIG.7 V Flyback PWM and Slope Compensation As shown in Figure 8, peak-current-mode control is utilized for flyback PWM. The SG6902 inserts a synchronized 0.5V ramp at the beginning of each switching cycle. This built-in slope compensation ensures voltage exceeds the stable operation for continuous-current-mode operation. When the IPWM voltage, across the sense resistor, reaches the threshold voltage, 0 ...
Page 18
... In the event of a protection condition and/or begins decreasing. PWM being disabled, the SS pin quickly discharges. Gate Drivers SG6902 output stage is a fast totem-pole gate driver. The output driver is clamped by an internal 18V Zener diode to protect the power MOSFET Product Specification SG6902 www.sg.com.tw • ...
Page 19
... SG6902 has two ground pins. Good high-frequency or RF layout practices should be followed. Avoid long PCB traces and component leads. Locate decoupling capacitors near the SG6902. A resistor (5 ~ 20Ω) is recommended, connected in series from the OPFC and OPWM, to the gate of the MOSFET. Isolating the interference between the PFC and PWM stages is also important ...
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... Green-Mode PFC / Flyback-PWM Controller www.DataSheet4U.com REFERENCE CIRCUIT © System General Corp. Version 1.3.1 (IAO33.0022.B3 www.sg.com.tw • www.fairchildsemi.com Product Specification SG6902 September, 2007 ...
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... Product Specification SG6902 Detail θ L Detail A Typ. Max. 0.104 0.012 0.092 0.016 0.008 0.508 0.299 0.050 0.419 0.050 ° 0.020X45 0.004 8° ...
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... Green-Mode PFC / Flyback-PWM Controller www.DataSheet4U.com © System General Corp. Version 1.3.1 (IAO33.0022.B3 www.sg.com.tw • www.fairchildsemi.com Product Specification SG6902 September, 2007 ...