Recently, I purchased a power supply that claimed a max current of 2A and 0~15V. So I wanted to test it. I had a 36 watts bulb (used in motor cycles), but that was too much. Then, I thought of the dummy load that is explained by Dave in his video blog.
My version is similar, but I changed certain components to my liking (and what ever was already available with me).
Following are changes: –
1. I used MCP6002 — rail-to-rail opamp (both input and output). Supply voltage = 5V. Using rail-to-rail opamp simplifies the hardware design a lot and using this opamp, I was able to control current all the way from 1mA to 1A (and more). I also tried using LM358 (pin compatible, so remove MCP6002 from socket and insert LM358). But then, my max current was limited. That is either due to the lower limits of inputs/ outputs for this opamp. I could tweak the resistor to make the circuit work, but then, I had a bunch of MCP6002 lying with me as well, so better use them.
For more detail: Dummy electrical Load
