HIP4081 was Re:Re:Black box/kerr

Hi,

I evaluated the HIP4081 and found it to be unsuitable because it was
a bad design. MOSFETs can generate voltages up to -5V below the rail
because of the extremely high di/dt involved. The HIP part went into
CMOS "latchup" and failed the MOSFET and itself in the process. I'd
stick with IR2104s. They have no vices.

Mariss

--- In CAD_CAM_EDM_DRO@egroups.com, "andrew abken" <kn6za@h...> wrote:
>
>
> Hello,
>
> No I did not do anything special, I lost lots of mosfets to find
out that
> I can get no where near the promised upper limit of 80 volts. As
long as I
> stay down at 30 volts all is cool. If I had it to do over again I
would
> never use this chip again. I am building a spindle drive, 100 volts
15 amps,
> that will be under pic servo control, but it will use the ir2104.
So far I
> have not had any problems in my limited testing.
>
>
> I admit it was a bad choice, and one I would love to change, but
as long
> as I stick with my 24 volt servos I will continue to use the drives.
>
>
> Andrew Abken
>
>
> >From: ballendo@y...
> >Reply-To: CAD_CAM_EDM_DRO@egroups.com
> >To: CAD_CAM_EDM_DRO@egroups.com
> >Subject: [CAD_CAM_EDM_DRO] HIP4081 was Re:Re:Black box/kerr
> >Date: Mon, 11 Dec 2000 02:51:45 -0000
> >
> >andrew wrote:
> > >I did not purchase his boards, but rather built my own servo
system
> > >with a combo of pic servo / hip4081 mosfet motor drivers.
> >
> >Andrew,
> >
> >Lotta people say bad things re: hip4081. Did you do anything
special?
> >Have you been running at load for awhile?
> >
> >Ballendo
> >
> >
> >
> >
> >Welcome to CAD_CAM_EDM_DRO@e...,an unmoderated list for the
> >discussion of shop built systems, for CAD, CAM, EDM, and DRO.
> >
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