I can take +/- 70v about 10amper to channel with 15 amp peak?
I could change etd 39 with etd 49 and change irf740, with irfm360 (400volt 23amper Rds 0.23 ohm). Is ok??????
Choice of oscillators and protection
The PCB can be adopted to work with a different oscillator as mentioned before due to the oscillator board and protection circuit is mounted on a separate pin header. This is plugged in the socket provided on the pcb. I also made plans to use different protection circuitry using either a Schmitt trigger or driving an SCR gate with both options pulling down pin 3 of the IR2153 to ground. However these type of protection brings out the need to reset by switching off the supply and waiting for the bulk cap to discharge until it can be switched on again. I prepared the prototype pcbs for these but have not been tried yet
Heat sink and cooling
A good heat sink is needed for the fets and output diodes as these are driven quite hard during the peak output. With the heat sink used the smps can handle the power easily if a small fan is included. I made a fan socket available for this reason. In my setup peak power could be held for quite a long time without things getting hot with the fan on. This was placed at the side to cool also the transformer
An auxiliary output of 12v-0-12v is provided capable of around 800mA. This is intended to drive a preamp stage or some protection circuit on an amplifier. I often see the need of a separate output for this reason.
The design voltage of the smps is 46-0-46 peak at 230 volts input. During my tests the output voltage went down to 78volts at 9.4 amps. The input voltage was 227vac with a power output of 730watts. The efficiency of the smps reached 90%.
IF ANYONE IS INTERESTED IN BUILDING THIS SMPS I WILL SEND THE PDF FILE PRIVATELY
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