From: Sean Breheny <shb7@cornell.edu>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Tue, 28 Jan 2020 17:32:16 -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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Any update? I'm really curious.

On Sat, Jan 25, 2020, 10:32 PM Sean Breheny <shb7@cornell.edu wrote:

> I agree - beware that power supplies which are isolated from earth ground
> may still have substantial capacitance to ground which can affect circuit=
s
> when you ground one of the nodes in the circuit.
>
> On Sat, Jan 25, 2020 at 5:58 PM Jason White <
> whitewaterssoftwareinfo@gmail.com> wrote:
>
>> Isolated differential probe for Vunregulated and "directly connected"
>> for PWM pulses out of H-Bridge. Power supply is isolated from earth
>> ground.
>>
>> I suppose I should try just the differential probe.
>>
>> On Sat, Jan 25, 2020 at 5:22 PM Sean Breheny <shb7@cornell.edu> wrote:
>> >
>> > How are you measuring  the voltage across the H-bridge? Are you using =
a
>> > differential probe? If not, where is the probe GND connected?
>>
>> -Jason White
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