From: Richard Prosser <rhprosser@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Thu, 23 Jan 2020 11:27:47 -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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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.co=
m>
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
> --
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