Thread: Suggested Resistor values for 3.3V resistor ladder?
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Unread 02-28-2011, 12:59 AM
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Re: Suggested Resistor values for 3.3V resistor ladder?
Quote:
Originally Posted by mikets View Post
Assumptions:
  • Vcc is the total voltage, whether its 5V or 3.3V.
  • Imax is the maximum current you can draw.
  • N is the total number of stages you want.
  • The input impedance of the analog channel is high enough that makes the current flowing through the analog input insignificant.
Rtotal = Vcc/Imax
R = Rtotal/(N - 1)
Round R up to the next one or more standard resistor value for good margin.
Thanks! I'll give this a whirl.

Mike