Note: The WBO2 project is defunct, and these pages are no longer being actively maintained.

The DIY-WB controller chip selection notes
Robert Rauscher July 2001

Devices in green are the better choices.
This is based on performance versus price.
Part #
Op-amps U2 & U4:      
    LM324 0c to 70c
    LM324A 0c to 70c
    LM2902 -40c to 85c 
    LM224 -25c to 85c
  LM224A -25c to 85c 
  LM124 -55c to 125c
  LM124A -55c to 125c
Analog Switch U3:  
Voltage references D5 & D11:  
  LM431BCZ 0c to 70c
  LM431BIZ -40c to 85c 
  TL431C 0c to 70c
  TL431AC 0c to 70c
  TL431I -40c to 85c
   TL431AI -40c to 85c
  LM431CCZ 0c to 70c
  LM431CIZ -40c to 85c
Voltage reference D8:  
The only concern with this device is the temperature range. 
Extreme accuracy is not required. 
  LM385-1.2 0c to 70c
  LM285-1.2 -40c to 85c 
  LM185-1.2 -55c to 125c

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