AnsweredAssumed Answered

AD7768-4 issue.

Question asked by JasonChien on Jul 1, 2016
Latest reply on Jul 14, 2016 by NiallM

Dear Sir:

                We tried to design AD7768-4 for our sensor circuit , But I have a issue from ADC input pin. When turn on AD7768-4    and AINx+ and AINx- are floating , we can measure 5.28V DC on those pin. when we remove VDDIO1.8V then 5.28V vanish. What's Wrong? Below is our condition on AD7768-4. BTW, Does AD7768-4 has power on sequence?

 

AVDD1A=5.1V

AVDD1B=5.1V

AVDD2A=5.1V

AVDD2B=5.1V

IOVDD=1.8V

REFx+=2.5V

REFx-=2.5V

MCLK =32MHz

 

Jason

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