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FAN7527B BOUNDARY MODE PFC CONTROL IC

FAN7527B BOUNDARY MODE PFC CONTROL IC
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FAN7527B BOUNDARY MODE PFC CONTROL IC - 1

©2003 Fairchild Semiconductor Corporation www.fairchildsemi.com Rev 1.0.2 Features • Internal start-up timer • Internal R/C filter eliminates the need for an external R/C filter • Very precise adjustable output over voltage protection • Zero current detector • One quadrant multiplier • Trimmed 1.5% internal band gap reference • Under voltage lockout with 3V of hysteresis • Totem pole output with high state clamp • Low start-up and operating current • 8-Pin DIP or 8-Pin SOP Applications • Electronic ballast • SMPS Description The FAN7527B provides simple and high performance active power factor correction. The FAN7527B is optimized for electronic ballasts and low power and high density power supplies which require minimum board size, reduced external components and low power dissipation. Because the R/C filter is included in the current sense block, the external R/C filter is not necessary. Special circuitry has also been added to prevent no load runaway conditions. Regardless of the supply voltage, the output drive clamping circuit limits the overshoot of the power MOSFET gate drive. It greatly enhances the system reliability. FAN7527B Power Factor Correction Controller 8-DIP 8-SOP 1 1

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 2

FAN7527B 2 Internal Block Diagram 1 INV 2 Vea(-) Error Amp Vref + - OVP Current Detector Isovp=30uA Idovp=40uA - + Vref Vm2 Vref~Vref+2.5V 2.25V Static OVP + - EA_OUT 6 GND Vm1 (Vm2 Vref) K Vmo · - = Multiplier + - Vm1 Vmo 0 ~ 3.8V 8pF 40k + - + - 2.5V Ref Internal Bias Timer R 7 Vcc 5 4 3 Vcc 8 Idet CS MULT Drive OUT Output 0.25V Veao(L)=2.25V R Q S UVLO 7.2V Zero Current Detector Current Sense Comparator 1.8V 2V 1.5V 11.5V 8.5V

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 3

FAN7527B 3 PIN Description Pin Number Pin Name Pin Function Description 1 INV Inverting input of the error amplifier. the output of the boost converter should be resistively divided to 2.5V and connected to this pin. 2 EA_OUT The output of the error amplifier. a feedback compensation network is placed between this pin and the INV pin. 3 MULT Input to the multiplier stage. the full-wave rectified ac voltage is divided to less than 2V and is connected to this pin. 4 CS Input of the PWM comparator. the MOSFET current is sensed by a resistor and the resulting voltage is applied to this pin. an...

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 4

FAN7527B 4 Absolute Maximum Ratings (Ta=25°C) Thermal Data Temperature Characteristics (-25°C Ta 125°C) Characteristics Symbol Value Unit Supply voltage VCC 30 V Peak drive output current IOH,IOL ±500 mA Driver output clamping diodes Vo > Vcc or Vo < -0.3V lclamp ±10 mA Detector clamping diodes ldet ±10 mA Error amp, multiplier and comparator input voltages Vin -0.3 to 6 V Operating junction temperature Tj 150 °C Operating temperature range Topr -25 to 125 °C Storage temperature range Tstg -65 to 150 °C Power dissipation 8-DIP Pd 1.1 W 8-SOP 0.8 Characteristics Symbol Value Unit Thermal...

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 5

FAN7527B 5 Electrical Characteristics VCC= 14V, -25°C Ta 125°C, unless otherwise stated. Characteristics Symbol Test Condition Min. Typ. Max. Unit < UNDER VOLTAGE LOCKOUT SECTION> Start threshold voltage Vth(st) Vcc Increasing 10.5 11.5 12.5 V UVLO hysteresis HY(st) - 2 3 4 V < SUPPLY CURRENT SECTION > Start-up supply current Ist Vcc = Vth(st) -0.2V 10 60 100 uA Operating supply current Icc Output not switching - 3 6 mA Operating current at OVP Icc(ovp) Vinv = 3V - 1.7 4 mA Dynamic operating supply current Idcc 50kHz, CI = 1nF - 4 8 mA < ERROR AMPLIFIER SECTION > Voltage feedback input...

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 8

FAN7527B 8 Typical Performance Characteristics (Continued) Figure 7. Start-Up Supply Current vs Temperature Figure 8. Error Amplifier Source Current Figure 9. Error Amplifier Sink Current Figure 10. Error Amplifier Input Bias Current Figure 11. Multiplier Gain vs Temperature Figure 12. ldet Threshold Voltage vs Temperature vs Temperature vs Temperature vs Temperature -25 0 25 50 75 100 125 0 10 20 30 40 50 60 70 80 90 100 Fig.7 Start-up Supply Current vs. Temperature Start-up Supply Current(uA) Temperature (Ž) -25 0 25 50 75 100 125 -5 -4 -3 -2 -1 0 Fig.8 E.A. Source CurrenT vs. Temperature...

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FAN7527B BOUNDARY MODE PFC CONTROL IC - 12

FAN7527B 8/16/03 0.0m 001 Stock#DSxxxxxxxx ÆÉ 2003 Fairchild Semiconductor Corporation LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be...

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