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From: pplante@netcom.com (P. Plantec)
Subject: Re: PWM chip
Message-ID: <pplanteCKM7AG.3zC@netcom.com>
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Date: Wed, 2 Feb 1994 20:51:37 GMT
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Anthony Hyde (ahyde@nmsu.edu) wrote:

: I have a PWM control chip.  It is a TL494.  Could someone please explain
: what the "DEAD-TIME CTRL" input is.  I am not sure how to use this chip
: but am interested in learning more about it.  Any information would
: be greatly appreciated.

Anthony, 
	I'm no expert, but with a pwm chip I believe the dead time can be 
uP controlled to allow rapid current decay when switching phases.  This 
helps to ensure proper operation at high step rates.
	Nevertheless, I have an Allegro 2916 pwm chip and I too am 
mystified as to how to use it.  I can see where it would be handy in 
half-step mode to maintain constant torque, but I still don't understand 
how to use it in microsteppining.  I'm going to post a queire.
-- 
************************************************************************
Peter Plantec                                     DreamScape Prods      
Beverly Hills, CA                                 Movies in the Mind
pplante@netcom.com                                Gargleing at the
                                                  fountain of Knowledge
