Hi everyone,
Most bench power supplies come with 1 to 3 outputs but I need 5 different voltages for testing a circuit (+3.3V, +5V, +12V, and +/-15V). I thought using my DP-832 for my +5V and +/-15V rails and another one (cheaper!) with 2 outputs for the +3.3V and +12V (which I don't own yet, BTW). The goal is to get a ballpark view of the power consumption for my circuit for each power rail in order to design a power supply to go with it.
This got a few questions popping in my head:
How the heck do I connect the ground(s)? Do I tie both PSU grounds together? I'm pretty sure this is a no go because it would cause a ground loop. Therefore, the "test" circuit would have 2 grounds that sould be isolated from each other because of the ground loop. Am I missing something here?
I bit more detail:
+3.3V: LCD display power rail (estimation: < 500mA).
+5V: Main power rail (MCU, logic, sensors, LEDs, etc) (estimation: 1.5 to 3A, but I can be totally wrong here).
+12V: Cooling fans power rail (estimation: ~ 1 to 2A depending on the fan(s)).
+/-15V: OpAmp supply rails (estimation: ~100 to 200mA).
Thanks for any light you can shed on this shadow.