Daewoo 2898ST, Service Manual

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2 8
STR-S5707 (Hybrid IC for a Switching Regulator)
(1) General Description
The STR-S5707 is a Hybrid IC with a built in power transistor and a separate excitation control IC,
designed for converter type switching mode power supply applications.
The IC is capable of quasi-resonant mode and requires small number of external component.
(2) Feature
• Small SIP isolated package : Resin sealed type (transfer mold)
• Lower power dissipation at a lighter load
• Many protection function : - Pulse-by-pulse over current protection
- Over-voltage protection with a latch
- Thermal protection with a latch
• These protection functions are incorporated and can be latched with an external signal.
(3) Block Diagram
(4) Pin Description
PIN NAME SYMBOL DESCRIPTION
1 Collector C Collector of power Tr
2 Ground GND ground (Emitter of power Tr)
3 Base B Base of power Tr
4 Sink SINK Base current (IS) input
5 Over-current OCP over-current sensing signal input
protection
6 Inhibit INH input for synchronizing OFF time
Latch and latch circuit operation
7 Sensing SENS constant voltage control signal input
8 Drive DRIVE Base drive current (ID) output
9 Vin VIN supply voltage for control circuit