> Curious if anyone has abused 74AC series logic in a way I am suggesting.
> Gauges in a lot of automobile instrument clusters use small stepper
> motors with gear reduction. They are typically four wire types with
> about 250 to 300 ohm windings. They'll work on 5 volts. 74AC logic is
> rated for 24 mA so this could be an OK match. And I can drive two gauges
> with one 74AC540. I know I can probably get away with driving directly

I have not done it with 74AC' but use 74HCT244 to drive small stepper (5 V,
unipolar) without problems.  IIRC, the motor had current draw ~ 50 mA. I
used 2 gates per coil.=20

Hope this helps,=20

Sergey

http://beaglerobotics.com
=20



--=20
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