AnsweredAssumed Answered

AD5206 inconsistent value settings

Question asked by Joef on Sep 11, 2017
Latest reply on Oct 23, 2017 by musach

I breadboarded a simple circuit to check the functionality of using the AD5206 in rheostat mode to simulate RTDs for a battery management system.  I find that the resistor setting is incorrect around 1/10 of the time when the same instruction is given.  

  • I cannot see any issues with the timing on a scope (attached).  I am running this pretty slowly.  The clock rate is only 33 Hz.
  • I cannot detect any extra pulses or noise on the CLK or CS signals.  
  • Vdd = 5V and Vss=0V.  
  • Am I clocking the circuit too slowly?  
  • The outputs are open circuit right now.  I am checking the resistance using a Fluke DMM.  
  • Also, I did a test tying Terminal B to Ground and Terminal A to Vdd to form a voltage divider but the results were the same.  
  • I see this effect across multiple channels and using two different devices.