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voltage divider output off from ADC

349 Views - Created 02/07/2020


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I have a voltage divider with the Vout connected to the ADC. The voltage of the Vout measured is 2.4V but when i try to read this from the ADC with the read_voltage function I am getting 1.8V. 


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The ADC Pi contains a voltage divider on each input so when you added your voltage divider to the ADC Pi it is working in series with the existing divider dropping the voltage lower than expected.

You can increase the voltage range on the ADC Pi inputs by adding a single resistor in series with the input.  We have a calculator you can use to find the correct resistor value for the voltage range you need.

AB Electronics UK Tech Support

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