Picoscope 2204a - RC circuit - wrong RC measure

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Tomas
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Picoscope 2204a - RC circuit - wrong RC measure

Post by Tomas »

Hello,
I have a Picoscope 2204a with P6060 probes.
Trying to measure the capacitor load time in an RC circuit and getting a different value from the theory-cal one.
Tried several RC components and values.

Example: RC circuit, R=200 ohms, C=150nF, Picoscope is generating an square, 2V, 400Hz signal.
The RC should be close to 30usec and I measure 110usec.

What could it be?

Thanks

bennog
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Re: Picoscope 2204a - RC circuit - wrong RC measure

Post by bennog »

The sig gen has a output resistance (i think 600 ohm)
so you have actually 800 ohm and 150 nf.

for this low values of your R you need to take this into account.

Benno

Tomas
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Re: Picoscope 2204a - RC circuit - wrong RC measure

Post by Tomas »

Thanks Benno, that's the point.

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