I'm using 2 times 7 turns prim, and 70 turns sec. No load (only about 1W for the voltage sensing feedback resistors ) the circuit draws about 2.2W. So now I got 209V 0.63A output 75% efficiency and 208V 0.17A 74% efficiency. Since the efficiency was crap with a first test (I used the 1N4007 for the bridge rectifier), maybe the output capacitor of 470uF 450V is to big, they were also getting hot. I made everything like your schematic and it worked! Except I put in a lm7818 for feeding the So, I don't think you saw my last post about a uc2845 ic, looks like they call it a flyback converter (what I was building), simple design but since my e-core transformers made anoying noise (can't really explain it, nothing to do with lose windings with toroids there was no problem) even at 48khz specialy with litle or no load, under 'heavy' load it was better, and after removing some secundary windings it was also better but the output voltage was dropping under higher load.

It is common practice to tie VC to VCC when VCC is below 20V. Similarly when the SG3525 outputs are fed to another driver or IGBT, VC must be selected accordingly, keeping in mind the required voltage for the device being fed or driven. Care must be taken to ensure that the maximum VGS breakdown voltage of the MOSFET is not crossed. For driving logic level MOSFETs, lower VC may be used. So when driving Power MOSFETs, VC should be within the range 9V to 18V (as most Power MOSFETs require minimum 8V to be fully on and have a maximum VGS breakdown voltage of 20V). The output drive voltage will be one transistor voltage drop below VC. VC must lie within the range 4.5V to 35V. It is connected to the collectors of the NPN transistors in the output totem-pole stage. Pin 13 is VC – the supply voltage to the SG3525 driver stage.

SG3525 has an under-voltage lockout circuit that prevents operation when VCC is below 8V, thus preventing erroneous operation or malfunction. Pin 15 is VCC – the supply voltage to the SG3525 that makes it run. I've mentioned this in the article above: I'd say they're pretty good and certainly good enough for your purpose. I've used ExpressPCB and PCB123 (a little bit of EAGLE as well). Go through the manual and start using it. There are other free PCB design software available as well. There are many free PCB design software you can use to design the PCB yourself.Ĭadsoft EAGLE (freeware with limitation): Try to use a low-ESR capacitor.ģ) Unfortunately, I don't have the PCB design for this. If it's higher than that and close to 400V, use 630V.Ģ) It is an electrolytic capacitor. A 400V capacitor would be good since I assume your output voltage would be lower than 330V. 1) Make sure the voltage is higher than the maximum output voltage.

Sg3525 ir2110 smps rarest