I've built an H-bridge circuit on a breadboard that powers a Traxxas EZstart motor. The motor runs optimally at 7.2 volts. I'm running it at 6v. It's based on the attached schematic. I'm using TIP122, TIP127 mosfets and 2N3904 transistors instead of what the schematic shows, but it all works fine.
I'm puzzled by one thing. I noticed that if I replace the resistors leading to the base of the PNP mosfets, I actually get less power out of the motor. See the attached schematic. I don't get the logic of why increasing the current to the base of the PNP Mosfets would have this effect. Can anyone explain?
I'm puzzled by one thing. I noticed that if I replace the resistors leading to the base of the PNP mosfets, I actually get less power out of the motor. See the attached schematic. I don't get the logic of why increasing the current to the base of the PNP Mosfets would have this effect. Can anyone explain?
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