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Raspberry Pi has several output voltages, GPIO outputs theoretically giving exactly 0V for False and exactly 3.3V for True, 3.3V line and 5V line. However, how precise are these outputs? Can the output voltage vary on the total load on the particular pin or total loads on all pins?

In particular, I need very precise ON-OFF 3.3V or 5V voltage. If GPIO output is not precise enough I intend to use 3.3V or 5V line via operator amplifier to get a stable and reliable voltage output as shown below.

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What is your opinion or advice on that? I tried to Google some useful information on that but found none.

Sampath Madala
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Pygmalion
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1 Answers1

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The Pi's GPIO are to set logic levels (on or off). They are not designed to be a voltage reference.

The 3V3 rail is regulated. You'd have to see the specs for your Pi model to find the actual regulator used. I doubt if it is calibrated or particularly stable.

joan
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