FSCQ-Series Green Mode Fairchild Power Switch (FPS™)
February 2006
FSCQ-Series
FSCQ0565RT/FSCQ0765RT/FSCQ0965RT/FSCQ1265RT/
FSCQ1465RT/FSCQ1565RT/FSCQ1565RP
Green Mode Fairchild Power Switch (FPS™)
Features
■
Optimized for Quasi-Resonant Converter (QRC)
■
Advanced Burst-Mode Operation for under 1W
■
■
■
■
■
■
■
■
■
■
Description
A Quasi-Resonant Converter (QRC) typically shows
lower EMI and higher power conversion efficiency com-
pared to conventional hard-switched converter with a
fixed switching frequency. Therefore, a QRC is well
suited for noise-sensitive applications, such as color TV
and audio. Each product in the FSCQ-Series contains an
integrated Pulse Width Modulation (PWM) controller and
a SenseFET, and is specifically designed for quasi-
resonant off-line Switch Mode Power Supplies (SMPS)
with minimal external components. The PWM controller
includes an integrated fixed frequency oscillator, under volt-
age lockout, leading edge blanking (LEB), optimized gate
driver, internal soft start, temperature-compensated pre-
cise current sources for a loop compensation, and self
protection circuitry. Compared with a discrete MOSFET
and PWM controller solution, the FSCQ-Series can
reduce total cost, component count, size, and weight, while
simultaneously increasing efficiency, productivity, and sys-
tem reliability. These devices provide a basic platform that
is well suited for cost-effective designs of quasi-resonant
switching flyback converters.
Standby Power Consumption
Pulse-by-Pulse Current Limit
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: 25µA)
Internal High Voltage SenseFET
Built-in Soft Start (20ms)
Extended Quasi-Resonant Switching
Applications
■
CTV
■
Audio Amplifier
Related Application Notes
■
AN4146: Design Guidelines for Quasi-Resonant
Converters Using FSCQ-Series Fairchild Power
Switch.
■
AN4140: Transformer Design Consideration for
Off-Line Flyback Converters Using Fairchild Power
Switch.
Ordering Information
Product Number
FSCQ0565RTYDTU
FSCQ0765RTYDTU
FSCQ0965RTYDTU
FSCQ1265RTYDTU
FSCQ1465RTYDTU
FSCQ1565RTYDTU
FSCQ1565RPVDTU
YDTU: Forming Type
VDTU: Forming Type
Package
TO-220F-5L (Forming)
TO-220F-5L (Forming)
TO-220F-5L (Forming)
TO-220F-5L (Forming)
TO-220F-5L( Forming)
TO-220F-5L (Forming)
TO-3PF-7L (Forming)
Marking Code
CQ0565RT
CQ0765RT
CQ0965RT
CQ1265RT
CQ1465RT
CQ1565RT
CQ1565RP
BVdss
650V
650V
650V
650V
650V
650V
650V
R
ds(ON)
Max.
2.2
Ω
1.6
Ω
1.2
Ω
0.9
Ω
0.8
Ω
0.7
Ω
0.7
Ω
©2006 Fairchild Semiconductor Corporation
1
www.fairchildsemi.com
FSCQ-Series Rev. 1.1.2
FSCQ-Series Green Mode Fairchild Power Switch (FPS™)
Pin Configuration
TO-220F-5L
5. Sync
4. Vfb
3. Vcc
2. GND
1. Drain
TO-3PF-7L
5. Sync
4. Vfb
3. Vcc
2. GND
1. Drain
Figure 3. Pin Configuration (Top View)
Pin Definitions
Pin Number
1
2
3
4
Pin Name
Drain
GND
Vcc
Vfb
Pin Function Description
High voltage power SenseFET drain connection.
This pin is the control ground and the SenseFET source.
This pin is the positive supply input. This pin provides internal operating current for
both start-up and steady-state operation.
This pin is internally connected to the inverting input of the PWM comparator.
The collector of an optocoupler is typically tied to this pin. For stable operation,
a capacitor should be placed between this pin and GND. If the voltage of this
pin reaches 7.5V, the over load protection triggers
,
which results in the FPS
shutting down.
This pin is internally connected to the sync detect comparator for quasi-resonant
switching. In normal quasi-resonant operation, the threshold of the sync
comparator is 4.6V/2.6V. Whereas, the sync threshold is changed to 3.0V/1.8V
in an extended quasi-resonant operation.
5
Sync
4
www.fairchildsemi.com
FSCQ-Series Rev. 1.1.2