sam_sdpl
Newbie level 3
hii,
In one of my flyback smps configuration working in non-isolated topology iam using current mirror based feedback instead of using optoco
upler. The circuit works fine , but under higher main voltage i.e. 40% of 230V. The trannsistor in current mirror Q2, Q3 and Q1 gets shorted which inturns destroys switcher IC. Drain and source voltage gets shorted in the switcher IC.
Please refer the feedback circuit attached . I am not very sure of the resistance values of R4 required to be kept.
And also suggest what other design factors are going to influence the performance of the circuit.
Switcher IC being used is Viper25 from ST.
Output voltage is 3.6V@400mA
Sam
In one of my flyback smps configuration working in non-isolated topology iam using current mirror based feedback instead of using optoco
upler. The circuit works fine , but under higher main voltage i.e. 40% of 230V. The trannsistor in current mirror Q2, Q3 and Q1 gets shorted which inturns destroys switcher IC. Drain and source voltage gets shorted in the switcher IC.
Please refer the feedback circuit attached . I am not very sure of the resistance values of R4 required to be kept.
And also suggest what other design factors are going to influence the performance of the circuit.
Switcher IC being used is Viper25 from ST.
Output voltage is 3.6V@400mA
Sam