Hi Guys, greetings from NZ. I've built one of these 0 - 30v Chinese Power supplies, & I'm starting to tear my hair out with it. I'm using it to supply 4v to a motor out of an old drill. ( It seemed the cheapest option at the time! ) The power supply works great on the Test Bench, using low value ( 2.7Ω ) 10W resistor as a load. The motor runs fine when supplied with 4v from my Test Bench PSU. But as soon as I connect the Chinese PSU to the motor, the PSU dies. Usually it's the 2 regulator transistors ( Q1, Q2 ) that go short, IC2 as well, sometimes. I've soldered a couple of capacitors across the motor terminals, just in case spikes were doing the damage.
Help!!! While I've still got some hair left!
Help!!! While I've still got some hair left!