Description

STRL472 is a one of STR-L400 series ICs which is made of integrated MOSFET and a controller chip for application in quasi-resonant switching power supply which are all in one package. The IC is characterizes with achieving high efficiency and low noise power supply system. STRL472 IC highly recommended for system requiring low-height, enough creepage isolation between high and low voltage terminals of SIP-10L model package should be at least 6.5mm.

SIP-10L one package pin-out for STRL472, the terminal pins are counted from left to right.

STRL472 IC has 10 pins but only 8 have terminals and functional.  6 input and 2 output pins, the non-inverting and inverting input pins are protected from overload.

Terminal 1 to 6 electrical characteristics in MOSFET: ON resistance, drain leakage current, drain source voltage, switching time. Terminal 8 to 10 control circuit electrical characteristics: power dissipation in control, operating start and stop voltage, circuit current in operation and non-operation.

STRL472 Specifications and features

The IC is characterized with high protection set of features which help achieve low component count and high performance in relation to cost power supply.  It has many built-in circuitries for protection and control.

• STRL472 is a power integrated circuit.
• Built-in oscillator which operates at low frequencies
• Current control mode

• Quasi-resonant operation
• Compensation of input at over current
• SIP10L full model package for home appliances (white goods) power supply.
• Straight lead  pitch 2.54mm
• Operates with low frequency of 50  OFF time, which help to reduce stress time on components during load-short and start-up
• It has several built-in protection features :

Over current protection (OCP): pulse by pulse

Over voltage protection (OVP): latch shutdown

Thermal shutdown protection (TSD): latch shutdown

Overload protection (OLP): latch shutdown 

Working principle of STRL472

For start-up operation the startup circuit detects voltage at the input terminal to affect start/stop operation of the power IC.

Constant voltage control circuit operation the current control mode is used to control the output voltage by selecting one with is stable and has superior transient responsibility.

Quasi-resonant operation the turning ON is done at Vds do reduce switching loss and noise. This results to low noise and achieves high efficiency.   

Application of STRL472

STRL472 Power IC has many applications because of it many features such as Quasi-Resonant type switching power supply with high efficiency.

White goods- home large appliances such as washing machine, refrigerator they use a lot of power.  

The power IC is also used in communication system, power supplies, LEDs drives, audio, induction cookers, computers, smart home and much other electrical and electronic equipment.  

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