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FSCQ0765RT
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
www.DataSheet4Up.coowmer 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
VFB Vcc
Drain
GND
Figure 1. Typical Flyback Application
©2004 Fairchild Semiconductor Corporation
Rev.1.0.1
FSCQ0765RT
Electrical Characteristics (SenseFET Part)
(Ta=25°C unless otherwise specified)
Parameter
Drain-Source Breakdown Voltage
Symbol
BVDSS
Zero Gate Voltage Drain Current
IDSS
Static Drain-source on Resistance (Note) RDS(ON)
www.DataSheet4UIn.cpoumt Capacitance
Output Capacitance
Ciss
Coss
Reverse Transfer Capacitance
Crss
Turn on Delay Time
td(on)
Rise Time
tr
Turn Off Delay Time
td (off)
Fall Time
tf
Total Gate Charge
(Gate-Source+Gate-Drain)
Qg
Gate-Source Charge
Qgs
Gate-Drain (Miller) Charge
Qgd
Condition
VGS = 0V, ID = 250µA
VDS = Max, Rating, VGS = 0V
VDS= 0.8*Max., Rating
VGS = 0V, TC = 85°C
VGS = 10V, ID = 2.3A
VGS = 0V, VDS = 25V,
f = 1MHz
VDD= 0.5BVDSS, ID= 7.0A
(MOSFET switching
times are essentially
independent of operating
temperature)
VGS = 10V, ID = 7.0A,
VDS = 0.5BVDSS (MOSFET
Switching times are essentially
independent of operating
temperature)
Min.
650
-
-
-
-
-
-
-
-
-
-
-
-
-
Typ. Max.
--
- 200
- 300
1.4 1.6
1415 1840
100 130
15 20
25 60
60 130
110 230
65 140
40 52
7 9.1
12 17
Unit
V
µA
µA
Ω
pF
ns
nC
Note:
1. Pulse test : Pulse width ≤ 300µS, duty ≤ 2%
5