A load off my mnd

[PerranOak]

I'd like to make an electronic load. Something simple with modest parameters, say, up to 1A and 25V or so.

Any recommendations for a nice circuit that you may have seen?

Thanks.

[JackJones]

There is the eevblog DC load, about as simple as you can get:



If you want something a little bit fancier, this Scullcom DC load is pretty good, highly recommend watching the videos.

[PerranOak]

Brilliant! Cheers and thank you.

[JackJones]

I have built both of those DC loads, in fact I think the eevblog version was one of my first projects. I think it might have been oscillating though, I remember hearing a buzzing sound coming from it at higher currents. Next time I powered it up it was dead. I didn't have a scope back then so couldn't check. Might make sense to put a series resistor to the gate and/or a snubber from the opamp output to the opamp negative input if you're going for the simpler design.

I also built the Scullcom version with minor modifications, like some different component choices and used a micro for it. I'm not a big fan of using Arduinos permanently in projects, it's much more professional to just use a micro. Nothing wrong with it though.

I'd suggest watching the whole series of the Scullcom videos if you go that route, because he does add quite a bit of functionality to the design over the videos.

[MarkF]

Here is mine.  For low currents you can get away without a fan.

Edit:  Updated circuit

[rdl]

The EEVblog version is worth looking at as a start. It's pretty simple and easy to build, but it usually oscillates. That's easily fixed as long as you have an oscilloscope to see what it's doing.

[PerranOak]

"Loads" to look at, thanks.