A constant current load using mosfet and LM358

In my below post I mentioned that I am building a bench PSU however I am still waiting for the parts to arrive. I decided to make a constant current load in order to test the electronic fuse and the power supply itself. I had built one before but the mosfet kept blowing after a short time and it was difficult to set the current. I had another go and successfully made one that supported a 1 amp load at 12 volts for over an hour without going up in smoke.

I checked online to see if I had got my circuit right and I had but it was just a bad choice of mosfet. I made a video of it as I have plenty of time on my hands due to the lockdown and I’ve been quite busy finishing projects or finding things to make out of old things I had laying around. A lot went onto ebay and what didn’t sell I threw out or destroyed for a bit of fun.

When the power supply is done I’ll post an update on it. There won’t be much to say as it uses pre built power supply modules but I will be adding some of my own modifications and enhancements such as the abforementioned electronic fuse.

One Reply to “A constant current load using mosfet and LM358”

  1. An update on this project, It’s been running for over 4 hours testing a power bank at a 1A load / 5V and works just fine.

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