I'm building a system based on an ATMega128A. My board (which only draws about 25 mA) works fine when running off my bench supply's 5V. When I switch to the chassis supply I'll be using in the finished product (a Mean Well RPS-400-24-TF), I can program/verify the MCU, but it doesn't run the program nor will the emulator work. The Mean Well is primarily a 24V supply, but it also has a 5V/1A standby output which I'd like to I use to power my board. This is what seems to be causing the problem. It produces an occasional 300 mV spike, but that's the only anomaly I can find, and that's well within the tolerance of the MCU. What else should I be looking for? Thanks for any tips.
Joined: Tue. Apr 1, 2003
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