FSCQ0765RT

Product Summary

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 PW 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.

Parametrics

Absolute Maximum Ratings,(Ta=25℃, unless otherwise specified):
(1)Drain-Source (GND) Voltage (note1),VDSS:650 V;
(2)Drain-Gate Voltage (RGS=1MΩ),VDGR:650 V;
(3)Gate-Source (GND) Voltage,VGS:±30 V;
(4)Drain Current Pulsed (note2),IDM:15 ADC;
(5)Single Pulsed Avalanche Energy (note3),EAS:570 mJ;
(6)Continuous Drain Current (Tc = 25℃),ID:3.8 ADC;
(7)Continuous Drain Current (TC=100℃),ID:2.4 ADC;
(8)Supply Voltage,VCC:20 V;
(9)Analog Input Voltage Range,Vsync:-0.3 to 13V;VFB: -0.3V to VCC;
(10)Total Power Dissipation,PD:45 W; (11)Operating Junction Temperature, TJ: +150℃;
(12)Operating Ambient Temperature, TA:-25 to +85 ℃;
(13)Storage Temperature Range, TSTG:-55 to +150 ℃;
(14)Thermal Resistance,Rthjc:2.6℃/W
Notes:
1. Tj = 25°℃ to 150℃
2. Repetitive rating: Pulse width limited by maximum junction temperature
3. L = 21mH, VDD = 50V, RG = 25Ω, starting Tj = 25℃

Features

(1)Optimized for Quasi-Resonant Converter (QRC);
(2)Advanced Burst-Mode operation for under 1 W standby power consumption;
(3)Pulse by Pulse Current Limit (5A);
(4)Over load protection (OLP) - Auto restart;
(5)Over voltage protection (OVP) - Auto restart;
(6)Abnormal Over Current Protection (AOCP) - Latch;
(7)Internal Thermal Shutdown (TSD) - Latch;
(8)Under Voltage Lock Out (UVLO) with hysteresis;
(9)Low Startup Current (typical : 25uA);
(10)Low Operating Current (typical : 4mA);
(11)Internal High Voltage SenseFET;
(12)Built-in Soft Start (20ms);
(13)Extended Quasi-resonant Switching for Wide Load Range

Diagrams

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