I am making a digital slot car controller. After maybe an hour of track time, the main power MOSFET (M1) died on me. Putting it on the scope with the motor running, there are transient spikes in the 50-60V range. The motors operate at 12V and can draw anywhere from 1A to 3A continuous, 8A peak. I added C4 across the power leads to hopefully smooth out the power across M1, but it doesn't seem to help much. Any advice on how to reduce the noise, or at least protect the M1 MOSFET? Feel free to point out anything else I may have done wrong. |
by SgtSnyder2
February 21, 2023 |
by SgtSnyder2
February 22, 2023 |
Have you tried a snubber network parallel to M1? And a faster diode D1 than 1N4004? |
ACCEPTED
+1 vote by FrankyDee March 02, 2023 |
Thanks for the reply, this is exactly what I ended up doing, and it works exceptionally well! I picked up some MUR460s, and put one across the motor leads and the other across M1. No more spikes, and only slight noise at M1s drain, miles from concerning. The voltage everywhere else is rock solid. |
by SgtSnyder2
March 09, 2023 |
You must log in or create an account (free!) to answer a question.
Anyone can ask a question.
Did you already search (see above) to see if a similar question has already been answered? If you can't find the answer, you may ask a question.
CircuitLab's Q&A site is a FREE questions and answers forum for electronics and electrical engineering students, hobbyists, and professionals.
We encourage you to use our built-in schematic & simulation software to add more detail to your questions and answers.
Acceptable Questions:
Unacceptable Questions:
Please respect that there are both seasoned experts and total newbies here: please be nice, be constructive, and be specific!
CircuitLab is an in-browser schematic capture and circuit simulation software tool to help you rapidly design and analyze analog and digital electronics systems.