Q0765RQ.pdf 데이터시트 (총 19 페이지) - 파일 다운로드 Q0765RQ 데이타시트 다운로드

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April 2009
FSQ0765RQ
Green-Mode Fairchild Power Switch (FPS™) for
Quasi-Resonant Operation - Low EMI and High Efficiency
Features
! Optimized for Quasi-Resonant Converter (QRC)
! Low EMI through Variable Frequency Control and AVS
(Alternating Valley Switching)
! High-Efficiency through Minimum Voltage Switching
! Narrow Frequency Variation Range over Wide Load
and Input Voltage Variation
! Advanced Burst-Mode Operation for Low Standby
Power Consumption
! Simple Scheme for Sync Voltage Detection
! Pulse-by-Pulse Current Limit
! Various Protection functions: Overload Protection
(OLP), Over-Voltage Protection (OVP), Abnormal
Over-Current Protection (AOCP), Internal Thermal
Shutdown (TSD) with Hysteresis, Output Short
Protection (OSP)
! Under-Voltage Lockout (UVLO) with Hysteresis
! Internal Startup Circuit
! Internal High-Voltage Sense FET (650V)
! Built-in Soft-Start (17.5ms)
Applications
! Power Supply for LCD TV and Monitor, VCR, SVR,
STB, and DVD & DVD Recorder
! Adapter
Related Resources
Visit http://www.fairchildsemi.com/apnotes/ for:
! AN-4134: Design Guidelines for Offline Forward
Converters Using Fairchild Power Switch (FPS)
! AN-4137: Design Guidelines for Offline Flyback
Converters Using Fairchild Power Switch (FPS)
! AN-4140: Transformer Design Consideration for
Offline Flyback Converters Using Fairchild Power
Switch (FPS)
! AN-4141: Troubleshooting and Design Tips for
Fairchild Power Switch (FPS) Flyback Applications
! AN-4145: Electromagnetic Compatibility for Power
Converters
! AN-4147: Design Guidelines for RCD Snubber of
Flyback
! AN-4148: Audible Noise Reduction Techniques for
Fairchild Power Switch Fairchild Power Switch(FPS™)
Applications
! AN-4150: Design Guidelines for Flyback Converters
Using FSQ-Series Fairchild Power Switch (FPS)
Description
A Quasi-Resonant Converter (QRC) generally shows
lower EMI and higher power conversion efficiency than a
conventional hard-switched converter with a fixed
switching frequency. The FSQ-series is an integrated
Pulse-Width Modulation (PWM) controller and
SenseFET specifically designed for quasi-resonant
operation and Alternating Valley Switching (AVS). The
PWM controller includes an integrated fixed-frequency
oscillator, Under-Voltage Lockout (UVLO), 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 a discrete MOSFET and PWM controller
solution, the FSQ-series can reduce total cost,
component count, size, and weight; while simultaneously
increasing efficiency, productivity, and system reliability.
This device provides a basic platform that is well suited
for cost-effective designs of quasi-resonant switching
flyback converters.
© 2008 Fairchild Semiconductor Corporation
FSQ0765RQ Rev. 1.0.1
www.fairchildsemi.com
Free Datasheet http://www.datasheet4u.com/

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Ordering Information
Product
Number
PKG.(5)
Operating
Temp.
Current
Limit
Maximum Output Power(1)
RDS(ON)
Max.
230VAC±15%(2)
Adapter(3)
Open
Frame(4)
85-265VAC
Adapter(3)
Open
Frame(4)
Replaces
Devices
FSQ0765RQWDTU TO-220F-6L -25 to +85°C 3.5A
1.6Ω
80W
90W
48W
70W
FSCM0765R
FSDM0765RB
Notes:
1. The junction temperature can limit the maximum output power.
2. 230VAC or 100/115VAC with doubler.
3. Typical continuous power in a non-ventilated enclosed adapter measured at 50°C ambient temperature.
4. Maximum practical continuous power in an open-frame design at 50°C ambient.
5. For Fairchild’s definition of “green” Eco Status, please visit:
http://www.fairchildsemi.com/company/green/rohs_green.html. Eco Status: RoHS.
© 2008 Fairchild Semiconductor Corporation
FSQ0765RQ Rev. 1.0.1
2
www.fairchildsemi.com
Free Datasheet http://www.datasheet4u.com/

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Application Diagram
AC
IN
Sync
PWM
FB VCC
Vstr Drain
GND
VO
FSQ0765R Rev.00
Figure 1. Typical Flyback Application
Internal Block Diagram
Sync
5
AVS
FB
4
0.35/0.55
VCC
Vref
VBurst
Idelay
IFB
3R
tON < tOSP
after SS
R
Soft-
Start
PWM
Vstr VCC Drain
6 31
OSC
Vref
VCC good
8V/12V
LEB
250ns
SQ
RQ
Gate
driver
VOSP
VSD
VOVP
LPF
TSD
LPF
SQ
RQ
AOCP
VOCP
(1.1V)
2
GND
VCC good
Figure 2. Internal Block Diagram
FSQ0765R Rev.00
© 2008 Fairchild Semiconductor Corporation
FSQ0765RQ Rev. 1.0.1
3
www.fairchildsemi.com
Free Datasheet http://www.datasheet4u.com/