Author Topic: Connecting the output from a function generator through a BNC cable to the input  (Read 508 times)

0 Members and 1 Guest are viewing this topic.

Offline john1998

  • Contributor
  • Posts: 9
  • Country: in
I am trying to work with the signals generated by a function generator using Raspberry Pi. Since Raspberry Pi does not have an inbuilt ADC, I used pcf8591. Now, I do not know how to feed the signal generated by the function generator into the input pins of pcf8591. Please help.

Offline Zero999

  • Super Contributor
  • ***
  • Posts: 14056
  • Country: gb
  • 0999
What part are you struggling with?

The input to the ADC needs to be biased at half the supply voltage and the signal generator must be loaded with 50Ohm, to avoid reflections.

This circuit will bias the ADC at 2.5V and has an input impedance of exactly 50Ohm, at high frequencies.

What's the lowest frequency of interest? This circuit has a cut-off frequency of just over 62Hz. If you need to go lower, increase the value of C1.

Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo