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SERVICE MANUAL
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1.7 Power module STR-G5653/6454R
Switch-mode Power Supply STR- G5653/F6654
The Series STR-G5653/F6654 is specifically designed to satisfy the requirements for increased
integration and reliability in off-line quasi-resonant flyback converters. The series incorporates a
high-precise error amplifying control and drive circuit with discrete avalanche-rated power MOSFET,
featuring fewer external components, small-size and standard power supply.
Covering the power range from below 25 watts up to 300 watts for 100/115/230 VAC inputs, and up to
150 watts for 85 to 265 VAC universal input, these devices can be used in a range of applications,
from battery chargers and set top boxes, to televisions, monitors, and industrial power supply units.
Cycle-by-cycle current limiting, under-voltage lockout with hysteresis, over-voltage protection, and
thermal shutdown protects the power supply during the normal overload and fault conditions.
Low-current startup and a low-power standby mode selected from the secondary circuit completes
a comprehensive suite of features. The series is provided in a five-pin overmolded SIP style package,
affording dielectric isolation without compromising thermal characteristics.
1) Features
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Flyback Operation with Quasi-Resonant Soft Switching for Low Power Dissipation and EMI
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Rugged Avalanche-Rated MOSFET
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Soft drive circuit MOSFET
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Adjustable MOSFET switching speed
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Choice of MOSFET Voltage and rDS(on)
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Full Over-Current Protection (no blanking)
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Under-Voltage Lockout with Hysteresis
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Over-Voltage Protection
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Direct Voltage Feedback
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Low Start-up Current (100
μ
Amax)
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Low-Frequency, Low-Power Standby Operation
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Overmolded 5-Pin Package
2). Circuit Block Diagram
Fig.18