Hi,
We have been manufacturing 12Volt Flyback SMPS ranging from 1Amp till 10Amp until now mainly for LED Lighting application.
Now, we would like to make 5Volt SMPS suited for Pixel LED application. The output current requirement will be 10Amp, 20Amp, 40Amp & 60Amp.
We are already using the UC3842B IC for our 12Volt - 10Amp circuit hence, we would like to use the same IC for making 5Volt - 10Amp & 5Volt - 20Amp circuits as well.
You may find the relevant technical specs mentioned below:
Input Voltage: 170 - 265V AC
Output Voltage: 5Volt (Constant)
Output current: 10Amp, 20Amp, 40Amp, 60Amp
Construction Type: Open Frame with external heatsink

Now, it is my understanding that we can use our existing circuit of 12Volt - 10Amp as base & make some changes in the components' values (ferrite transformer, output capacitors, etc.) to get 5Volt - 10Amp & 20Amp outputs respectively. The question is, what all need to be changed & is there any design tool available to do the same?

Secondly, is it even safe to design 5Volt - 20Amp in Flyback topology with UC3842B DIP IC?

Thirdly, for higher current output models of 40Amp & 60Amp, I am looking into forward converter topology with TL494 IC since it would be impractical to design the same in Flyback. But, I am not able to get my hands on detailed schematics & ferrite designs for the same. So, if anyone could help with any design tool for the same or schematics then it would be a boon for me.

 

If you want higher current output, you need to change the pulse transformer, mosfet driver, output diodes,and possibly the pcb track design.. 5V @20A is 100W you're probably going to need a metal ventilated case also..

 

If you want higher current output, you need to change the pulse transformer, mosfet driver, output diodes,and possibly the pcb track design.. 5V @20A is 100W you're probably going to need a metal ventilated case also..

Hello, we already have an Aluminum ventilated case for these cicrcuits that act as heatsink for output diode & Mosfet. Now, for other changes, is there any design tool available for UC3842B IC that we can use so that there is no scope for hit & trial?