> > if the motor produces back EMF (i.e. no electronics in it, just brushes=
)
> > then I think you will be very concerned.
>=20
> There is no observable problems but I guess I will attach a flywheel
> diode to motor. Thanks for the suggestion.

A single flywheel diode is suitable if motor operated in one direction only=
.... but you=20
mentioned the motor is connected between two PIC I/O lines, presumably so y=
ou=20
can operate the motor in forward or reverse. A single diode would be forwar=
d biased=20
in one direction - shorting the motor. So then you need 4 x diodes in a bri=
dge=20
configuration. And they need to be Schottky diodes to operate before the PI=
Cs in=20
built protection diodes operate.

What about over current protection if the motor stalls?

--=20
Brent Brown, Electronic Design Solutions
16 English Street, St Andrews,
Hamilton 3200, New Zealand
Ph: +64 7 849 0069
Fax: +64 7 849 0071
Cell: +64 27 433 4069
eMail:  brent.brown@clear.net.nz



--=20
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