Re: N channel Mosfet H bridge drive

From: Paul E. Bennett (peb_at_amleth.demon.co.uk)
Date: 03/11/04 

Date: Wed, 10 Mar 2004 23:27:40 +0000 (UTC)

In article <404F4380.202A7983@autometer.de>
           tilmann.reh@autometer.de "Tilmann Reh" writes:

> Richard schrieb:
>
> > I am building 2 H bridges to drive a bipolar stepper motor controlled by a
> > PIC . I would like to apply 50 to 80 volts. I understand that there are H
> > bridge drivers for the mosfets like HIP4081A. But find them a bit costly
> > almost $10USD a piece and I need 2 pieces. Is there an alternative to make a
> > charge pump circuit to solve the problem of switching on the upper channel
> > FETs?
>
> a) no need to post this three times.
> b) look at IR2111 from IRF.

Just completing a design myself. Switched mode psu (very low power)
for the high level FET gate drives, opto-isolators for switching the
FETs on.

The benefit is less dependence on future supply of specialist chips
and better isolation between logic drive and FET stages. Then, some
applications of my bridges are dealing closer to 1kV. Should be
fairly standard for most of you guys unless you are all getting lazy. 

-- 
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