However, the duty cycle is lesser and is limited to 50%. It has an operating frequency of 80-90 kHz and has IRF2153 control circuit which is very much similar to that of US3842. The proposed Switched power supply 2x 50V 350W operates in single switch forward topology. The number of turns and the core which is found in PC supply is not a critical factor.Īdditionally, the 6k8 resistors at the output section is used to discharge capacitors after it is switched off and this way it helps to prevent the voltage increase during no load. The chokes used in the design will facilitate removal of RF output ripple. Moreover, to ensure low leakage inductance and full voltage output, the first half of the primary is wounded in 20 turns followed by the secondary wound.Īlso to assure safety in the system, do be sure to connect the output (center tap 0V) to the earth. This same phenomenon can be found in AT/ATX power supply unit of a computer. The use of Zener diode (15V) ensures voltage stabilization and the operating frequency is set to 50 kHz (approx.).Īt the point of the input, I have placed a thermistor to force a check on the peak current when the capacitor is getting charged. The ripple at full load is recorded below 2V.

The IR2153 is powered by a power resistor of 27K 6W. My power supply relies on two N MOSFET and run by IR2153 integrated circuit. Written and Submitted by: Dhrubajyoti Biswas Mosfets as Power Devices

Smps disable output protection