SITRONICS 25F83, Service Manual

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SERVICE MANUAL
1.6 Switch-mode Power Supply STR- F6454R/F6656
T F6454R/F6654 is specifically designe d
in esonant fly rs. The series incorporates a
high rive circuit with discrete avalanche-rated power
MOSFET, featuring fewer external components, small-size and standard power supply.
Cov s up to 300
to sal input, these devices can be used in a range of
app d set top boxes, to t
sup
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 compre s suite f features. The series is provided in a five-pin overmolded SIP style
package, affording dielectric isolation without compromising thermal characteristics.
(1) Features
·
Flyback Operation with Quasi-Resonant Soft Switching for Low Power Dissipation and EMI
·
Rugged Avalanche-Rated MOSFET
Soft drive circuit MOSFET
Adjustable MOSFET switching speed
·
Choice of MOSFET Voltage and r
DS(on)
·
Full Over-Current Protection (no blanking)
·
Under-Voltage Lockout with Hysteresis
·
Over-Voltage Protection
·
Direct Voltage Feedback
·
Low Start-up Current (100
μ
Amax)
·
Low-Frequency, Low-Power Standby Operation
·
Overmolded 5-Pin Package
he Series STR- d to satisfy the requirements for increase
tegration and reliability in off-line quasi-r
-precise error amplifying control and d
back converte
ering the power range from below 25 watt watts for 100/115/230 VAC inputs, and up
elevisions, monitors, and industrial power
150 watts for 85 to 265 VAC univer
lications, from battery chargers an
ply units.
hen ive o
30