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Author Topic: Quick question about DC motor  (Read 1189 times)

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Offline I-Jeff-ITopic starter

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Quick question about DC motor
« on: December 24, 2009, 07:16:53 PM »
Hi I have a quick question.  I just hooked a DC motor up to an L293D H-bridge so that two buttons spin the motor in one direction or the other.  Sometimes though, I need to spin the motor a little bit to get it started.  When I press the button it twitches, but doesn't start moving.  Other times, it works fine, usually after it is already spinning.  Is this normal?  Is there an easy fix to this?

Offline SmAsH

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Re: Quick question about DC motor
« Reply #1 on: December 24, 2009, 07:37:26 PM »
Hmm, do you know what the stall current of the motor is? It might be that the h-bridge cant supply the motor with enough juice to start it but it has enough to spin it...
Howdy

Offline I-Jeff-ITopic starter

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Offline SmAsH

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Re: Quick question about DC motor
« Reply #3 on: December 24, 2009, 08:18:56 PM »
Well, the page doesn't say what any of the info apart from voltage is :-\
The H-bridge can supply 600mA and 1200mA at peak...
Unless we can get a ballpark figure of the motors current draw this will be a hard one to figure out.
Have you tried putting one motor on both of the channels to double output current?
Howdy

Offline I-Jeff-ITopic starter

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Re: Quick question about DC motor
« Reply #4 on: December 24, 2009, 09:04:40 PM »
wow that worked, thanks a lot.  I guess I should have checked out the specs first :/ thanks again!

Offline SmAsH

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Re: Quick question about DC motor
« Reply #5 on: December 24, 2009, 09:11:59 PM »
Anytime :)
Howdy

 


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