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I need to supply +9V to three stepper motors on a breadboard with driver carriers (see parts below). Its too much for my raspberry pi to handle, apparently. I was able to power and control a single driver, so I know my setup is good.
I tried using an arduino power supply to drive them (+9V, 0.664A), but when its under load, the voltage seems to drop below +3V and nothing works.
I need to find a power source (not battery) for this. I'd prefer not ordering anything (short on time). Any suggestions, or tips to get the arduino supply to work properly?