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Lab power supply with DPS3005 module

 

This is a lab power supply I put together back in 2018 with one DPS3005 module. It is easily the most used piece of equipment in the lab, so much that it is permanently on.

The module itself is nothing but a DC-DC converter capable of 30 V and 5 A, providing a simple user interface, and isolated USB control (which I've never really needed). The output is pretty noisy as one might expect, see discussion here. An LC filter reduced some of that noise significantly. I'll have to come back to it and re-do it with smd capacitors, yet I have no real need. My other lab supply has way lower noise.

I first used a cheap swithcing supply to power the module, but it lasted a mere week or so. I later substituted it for an unregulated dc supply using a transformer I bought at the local flea market. The case I made for it being wood, I added a small fan in the back. I quickly added a simple two-transistor temperature controller because of the noise. With all fans running (power supplies, scope, a fan to blow soldering smoke...), noise becomes quite bothersome.






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