Re: eQADC operation on MPC5554

Randy,
  We did try using the calibration suggested in the application 
note.  It only removed about 0.04V of the offset.  The 0.850V 
remained.
Joe
--- In [email protected], "Dees Randy-rsaf30" <randy.dees@...> 
wrote:
>
> are you performing calibration? see AN 2989 - Design, Accuracy, and
> Calibration of Analog to Digital Converters on the MPC5500 Family.
> http://www.freescale.com/files/32bit/doc/app_note/AN2989.pdf
> 
> ________________________________
> 
> From: [email protected] [mailto:[email protected]] On 
Behalf
> Of JVB1_wow
> Sent: Tuesday, November 14, 2006 11:37 AM
> To: [email protected]
> Subject: [MPC500] eQADC operation on MPC5554
> 
> 
> 
> Hello,
> I am designing a system with the MPC5554 micro-controller. We are
> planning on using the eQADC. Checkout of the prototype hardware 
shows
> a large offset voltage of around -0.900V. The measured data in
> perfectly linear just offset by this bias. Anyone seen this before? 
> Thanks.
> 
> Joe
> 
> .
>  
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>  
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