Daewoo DTL-2950K, Service Manual

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CP-650 Service Manual
DTV R&D Europe 31
4.6 STR – W6754
4.6.1 GENERAL DESCRIPTION
The STR-W6700 series is a Hybrid IC (HIC) designed for Quasi-Resonant type Switching Mold
Power Supply built-in a Power MOSFET and Control IC.
4.6.2 FEATURES
operation mode turns blocking oscillation by reducing output voltage at stand-by mode.
In addition to the existing Quasi-Resonant Operation, the Bottom-Skip Function is added in
order to be efficient from light to medium load.
Soft-Start Operation is provided at the SMPS start-up.
Switching noise is reduced by Step-Drive Function.
Avalanche energy of the MOSFET is guaranteed.
Overcurrent Protection (OCP), Overvoltage Protection (OVP), Overload Protection (OLP),
and Maximum ON-Time control circuits are incorporated.
It is possible to save the SMPS design time by utilizing the present designs and evaluation
processes.
4.6.3 BLOCK DIAGRAM
D
S/GND
OCP/BD
V
CC
４ ４
３ ３
FB
＋
－
＋
－
Start
Stop
Burst
R
S
Q
Reg&
Iconst
OVP
DRIV E
Reg
１ １
７ ７
Abnormal
latch
S
R Q
FB
－
＋
＋
－
OCP
＋
－
BSD
＋
－
BD
Bottom Selector
Counter
５ ５
SS/OLP
－
＋
OLP
Delay
６ ６
S
R
Q S
R
Q S
R
Q
OSC
MaxON
Soft Start
Burst
Control Burst
Control