hello, i am modifying a laptop flyback PSU for charging car batteries, i can modify the output from 19.5v to 13.8v switchable to 14ish volts while keeping the voltage at the aux winding for the PWM control IC within operating range.
the pwm controller monitors current through the mosfet source resistor about 1V. i want to know the relationship between the input current [through the mosfet] and the output current in flyback mode. is it possible to modify the mosfet source resistor to reflect the desired output current?
trafo turns ratio is about 6.8:1 (correct me if im wrong), the voltage across the trafo secondary at the charging stage is -46v and at the flyback/dumping phase its +19v (stock). rectified mains voltage is 311v
i want to effectively limit the charging current at 5A or 3A [a depleted cell will definitely draw a lot so i want to limit it]. using a CCS at the output seems like a very inefficient way.
thank you very much!
the pwm controller monitors current through the mosfet source resistor about 1V. i want to know the relationship between the input current [through the mosfet] and the output current in flyback mode. is it possible to modify the mosfet source resistor to reflect the desired output current?
trafo turns ratio is about 6.8:1 (correct me if im wrong), the voltage across the trafo secondary at the charging stage is -46v and at the flyback/dumping phase its +19v (stock). rectified mains voltage is 311v
i want to effectively limit the charging current at 5A or 3A [a depleted cell will definitely draw a lot so i want to limit it]. using a CCS at the output seems like a very inefficient way.
thank you very much!
, i will try it out and tweak it.