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luciana
Posts: 4
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I have a variable +-10V DC signal, and a +-5V ADC range. How can I acquire the signal properly?

 
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Henrik_Volkers
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Re: I have a variable +-10V DC signal, and a +-5V ADC range. How can I acquire the signal properly?

Luciana,

use a voltage divider. The simples form is build with two resistors. In your case two resistors of the (exactly) same value.
Connection is (Signal)-(Resistor1)-(ADCinput)-(Resistor2)-(SignalGround)
Depending on your DC Signal source and the input resistant of your ADC the value of your resistors should be in a range of from 10k up to 1M.
47k resistors are a good starting point :-)
Since you said it is DC you don't have to care about frequency compensation.
Error calculation will be your homework
Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

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