From: Richard Prosser <rhprosser@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Thu, 23 Jan 2020 11:30:40 -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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Also, does the motor perform the same in both directions - try swapping the
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
>> --
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