I have an application involving a small DC gear motor rotating slowly (~ 5 RPM). I'm using it kind of like a stepper in that it rotates until a sensor detects the right position and then it has to stop. I've been playing around with an L293 bridge chip which has a fast stop mode that stops the motor faster than just killing the power. The L293 data sheet doesn't say what the chip is doing to stop it so fast. It's not reversing the current because I don't have it hooked up that way. An app note says only that the motor is "shorted by one of the transistors." It's still not clear to me what's going on. I'd like to understand since, if I can duplicate it with one or two transistors, I'd rather do that than use the L293. Can anyone clue me in? Thanks.
Joined: Tue. Apr 1, 2003
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