exam (discuss.tchncs.de)
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I bought a PWM Dimmer based on a 555 from AliExpress to regulate the brightness of a 12V 1A 1 meter LED strip, I already built one myself years ago on a perfboard but this one was the exact dimensions I needed for a project. I built mine from components from AliExpress and components found in old electronics so I thought nothing...
Since I never understood op-amps from reading or practicing problems I wanted to build a circuit to probe around and use different resistor values to set the amplification....