i designed 230V AC to 12v 5A SMPS based on UC3842 forward converter, which works fine but i want output short circuit or overcurrent protection through pin 3 but as my current sense resistor is on the primary side so primary side equivalent of 5A never reaches enough to give 1V to pin 3 and thus short circuit or overcurrent never works and heats up the mosfet (IRF740), i also tried a Schmitt trigger based on 2 pnp transistors which works fine on low input voltage (24V DC ) but it only hiccups the circuit instead on tripping. my only goal is to trip the supply on output short circuit or current >5A. How should i do that? will appreciate any help from you....
voltage divider of 1.8k and 8k to pin 3 is not included in the circuit.
it is my first ever question on any forum so forgive my shortcomings..
voltage divider of 1.8k and 8k to pin 3 is not included in the circuit.
it is my first ever question on any forum so forgive my shortcomings..
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