Part Number: CQ0765RT, FSCQ0765RT
Function: Green Mode Fairchild Power Switch
Package: TO-220F-5L Type
Manufacturer: Fairchild Semiconductor
Drain In general, Quasi-Resonant Converter (QRC) shows lower EMI and higher power conversion efficiency compared to the conventional hard switched converter with a fixed switching frequency. Therefore, it is well suited for applications that are sensitive to the noise, such as color TV and audio. The FSCQ0765RT is an integrated Pulse Width Modulation (PWM) controller and Sense FET specifically designed for Quasi-resonant off-line Switch Mode Power Supplies (SMPS) with minimal external components. The PWM controller includes integrated fixed frequency oscillator, under voltage lockout, leading edge blanking (LEB), optimized gate driver, internal soft start, temperature compensated precise current sources for a loop compensation and self protection circuitry. Compared with discrete MOSFET and PWM controller solution, it can reduce total cost, component count, size and weight simultaneously increasing efficiency, productivity, and system reliability. This device is a basic platform well suited for cost effective designs of Quasi resonant switching flyback converters.
www.fairchildsemi.com Green Mode Fairchild Power Switch (FPSTM) for Quasi-Resonant Switching Converter Features • Optimized for Quasi-Resonant Converter (QRC) • Advanced Burst-Mode operation for under 1 W standby power consumption • Pulse by Pulse Current Limit (5A) • Over load protection (OLP) – Auto restart • Over voltage protection (OVP) – Auto restart • Abnormal Over Current Protection (AOCP) – Latch • Internal Thermal Shutdown (TSD) – Latch • Under Voltage Lock Out (UVLO) with hysteresis • Low Startup Current (typical : 25uA) • Low Operating Current (typical : 4mA) • Internal High Voltage SenseFET • Built-in Soft Start (20ms) • Extended Quasi-resonant Switching for Wide Load Range OUTPUT POWER TABLE PRODUCT FSCQ0765RT FSCQ1265RT FSCQ1565RT 230VAC ±15%(2) Open Frame(1) 100 W 170 W 210 W 85-265VAC Open Frame(1) 85 W 140 W 170 W FSCQ0765RT Table 1. Notes: 1. Maximum practical continuous power in an open frame design at 50°C ambient. 2. 230 VAC or 100/115 VAC with doubler. Typical Circuit Application • CTV • DVD Receiver • Audio Power Supply AC IN Vo
FSCQ0765RT PWM Sync VFB GND Vcc Figure 1. Typical Flyback Application Rev.1.0.1 ©2004 Fairchild Semiconductor Corporation FSCQ0765RT Internal Block Diagram Sync 5 + Vcc 3 Quasi-resonant (QR) switching controller + Drain 1 Threshold – fs – 9V/15V Soft start 4.6V/2.6V : Normal QR 3.0V/1.8V : Extended QR Vcc good Auxiliary Vref Normal operation VBurst Burst mode Controller Normal operation Vref IBFB Vref IFB Burst Switching Vref IB OSC Main bias Internal bias Vcc FB 4 Idelay PWM S Q 2.5R R R Q Gate driver LEB 600ns VSD Sync Vovp Vcc good S Q Q R Q Q R S AOCP 2 GND TSD Power off Reset Vocp Figure 2. Functional Block Diagram of FSCQ0765RT 2 FSCQ0765RT Pin Definitions Pin Number 1 2 3 Pin Name Drain GND Vcc Pin Functio […]