From: Jason White <whitewaterssoftwareinfo@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Thu, 23 Jan 2020 11:42:29 -0800
Subject: Re: [EE] H-Bridge supply voltage spike only in "reverse" (not
 forward)
Thread-Topic: [EE] H-Bridge supply voltage spike only in "reverse" (not
 forward)
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Motor performs the same with leads swapped. I have a batch of 10 "virgin"
pcbs that all do the exact same thing.

On Thursday, January 23, 2020, Richard Prosser <rhprosser@gmail.com> wrote:

> Also, does the motor perform the same in both directions - try swapping t=
he
> leads to the motor also.
> RP
>
> On Fri, 24 Jan 2020 at 08:27, Richard Prosser <rhprosser@gmail.com> wrote=
:
>
> > Have you tried swapping the mosfets &/or drivers around. Something isn'=
t
> > right.
> >
> > RP
> >
> > On Fri, 24 Jan 2020 at 08:09, Jason White <
> > whitewaterssoftwareinfo@gmail.com> wrote:
> >
> >> Hello everyone,
> >>
> >> I am encountering the following. The supply voltage line to my
> >> H-Bridge is rising only when the H-Bridge is running a motor in
> >> "reverse." In forward the supply voltage is unaffected.
> >>
> >> Intuitively I am having trouble understanding why this should be. I
> >> lack a decoupling capacitor on the supply line, but do have a zener.
> >>
> >> I have attached a schematic of the circuit.
> >>
> >> I will send the forward and reverse waveforms in two follow up emails
> >> to avoid hitting the file size attachment limits.The waveforms will
> >> show supply voltage and voltage across the H-Bridge.
> >>
> >> --
> >> Jason White
> >> --
> >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> >> View/change your membership options at
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> >>
> >
> --
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