FSCQ0765RT Datasheet, PDF (1/24 Pages) Fairchild Semiconductor – Green Mode Fairchild Power Switch (FPS) for Quasi-Resonant Switching Converter

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FSCQ0765RT
Green Mode Fairchild Power Switch (FPS^TM) 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
Application
• CTV
• DVD Receiver
• Audio Power Supply
OUTPUT POWER TABLE
PRODUCT
230VAC ±15%⁽²⁾
Open Frame⁽¹⁾
85-265VAC
Open Frame⁽¹⁾
FSCQ0765RT
100 W
85 W
FSCQ1265RT
170 W
140 W
FSCQ1565RT
210 W
170 W
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
Vo
Description
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, produc-
tivity, and system reliability. This device is a basic platform
well suited for cost effective designs of Quasi resonant
switching flyback converters.
AC
IN
Sync
FSCQ0765RT
PWM
V_{FB Vcc}
Drain
GND
Figure 1. Typical Flyback Application
©2004 Fairchild Semiconductor Corporation
Rev.1.0.1