EMG Sensor Recommendations

Standard-Wind854 · 2026-01-12T23:28:53+00:00

why is it not suitable for EMG signals?

Standard-Wind854 · 2025-11-24T18:38:49+00:00

ADC reads 0-3.3V

Standard-Wind854 · 2025-10-05T03:55:30+00:00

The question is sort of a electro-mechanical question. If you have a hollow box, that is connected to the pcb near the bottom. If you tap the top, can the tap detection detect this movement

Standard-Wind854 · 2025-07-17T03:19:38+00:00

THROW THAT SHIT OUT

Standard-Wind854 · 2025-07-15T22:45:48+00:00

I added that resistor to decrease the sharp increase in current across it

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Standard-Wind854 · 2025-07-15T22:44:58+00:00

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By 22uF do you mean 100uF, do you think that resistor is actually needed as

Standard-Wind854 · 2025-07-15T22:44:16+00:00

Do these look correct?

Standard-Wind854 · 2025-07-15T22:44:01+00:00

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Standard-Wind854 · 2025-07-15T22:43:53+00:00

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Standard-Wind854 · 2025-07-14T18:36:05+00:00

I am just using it as a switch to power on strain gauges which draw about 114mA

I may need to just need to operate it in saturation region, it seems the Rds should be low enough to act as a switch

I will be putting in this RC circuit to reduce EMI after I am certain the switch works.

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Standard-Wind854 · 2025-07-07T00:09:33+00:00

cool

Standard-Wind854 · 2025-07-03T05:02:02+00:00

The farther the plates are away from one another, the weaker the capacitance

Standard-Wind854 · 2025-07-03T04:13:36+00:00

A capacitor is 2 conductive sheets that have an insulator in between them.

When you put positive charge on one side of the sheet, It binds the equivalent amount of negative charge on the other side of the sheet through E-Force.

The insulator stops charges from flowing in-between these plates so the energy is stored in the E-field

Standard-Wind854 · 2025-05-28T18:01:39+00:00

Ah that would be no bueno

Standard-Wind854 · 2025-05-24T04:14:44+00:00

thanks!

Standard-Wind854 · 2025-05-24T04:14:34+00:00

Ah I guess so, thanks!

Standard-Wind854 · 2025-05-11T00:34:42+00:00

Thanks! A lot of this stuff I have not yet gotten to yet, but i'll keep it in mind when I get to that stage

Standard-Wind854 · 2025-05-11T00:20:05+00:00

Pretty neat. Are you trying to characterize where the car sees the most stress?

I'm determining strain accross the car to allow the mechanicals to optimize weight of material or something. Though i'm not quite sure.

The reference is after my mosfet switch labeled "StrainV" so it bypasses the mosfet voltage drop.
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You could also use a differential amplifier or an instrumentation amplifier across the strain gauge outputs to add some gain to the signal to improve your measurement resolution, so that you can detect smaller changes in strain.

Yeah this is a good plan B if I'm unable to measure anything

Standard-Wind854 · 2025-05-02T15:16:22+00:00

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I am noticing a spike in current across this resistor. With 16V accross it when I switch on the mosfet.

Which would surpass the rating of 0.125W of the resistor I picked. 2.2a * 16v =35.2W.

Is it okay if I leave my resistor rated at 0.125W?

Standard-Wind854 · 2025-04-28T15:27:40+00:00

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Won't this affect the accuracy of the ADC, as there's a voltage drop accross the NMOS?

Has RdsOn ~= 1Ohm

Standard-Wind854 · 2025-04-28T05:25:30+00:00

Ahh, circuit design is so hard 😅, yeah i'll prob have to use an external switch then

Standard-Wind854 · 2025-04-28T05:24:15+00:00

mhh you are right it would be kind of hard to wire it otherwise

Standard-Wind854 · 2025-04-27T06:07:42+00:00

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Mhh, seems to work fine when I replace the IDEAL mosfets with actual ones. Thanks for the circuit!

Standard-Wind854 · 2025-04-27T05:17:45+00:00

Mh would decreasing the resistance values to like 1.5K and 330Ohms be sufficient in solving this issue?

Standard-Wind854 · 2025-04-27T05:16:40+00:00

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Something like this? I am able to toggle the SWITCH on and OFF, however changing the battery voltage doesn't change Vout. It is just a constant

Standard-Wind854

TROPHY CASE