AnsweredAssumed Answered

AD7949 CFG and Ref Out

Question asked by fatihcavdarci on Feb 24, 2017
Latest reply on Mar 6, 2017 by Gnib

Hello,

I need help about AD7949 adc. I send CFG register the value AdcCFG = 0x3FC4: 

* Overwrite contents of register

* Unipolar, INx referenced to GND

* IN7, full BW

* Internal reference, REF = 2.5 V output, temperature enabled

* Scan IN0 to IN[7:0] (set in CFG[9:7]), then temperature

* Read back current configuration at end of data

 

Order of write/read as below (I use timing RAC. ):

Write CFG >> Read null >> Read Data 0 to7 >> Read CFG >> Finally Read Temp.

Question1: Is the data read/write order true. Should I read CFG before or after Temp read.(I read true CFG read back before temp. ReadCFG = 0x3FC4)

Question2: Thats all ok. But when I measure the voltage on ref or ref buffer pin (No: 2.5V or 4.096V)???

Question3: I read temperature hex value: 0x0363 at room temp(~24-25'C) what is the meaning or calculation for temp.

Thanks for all answers...

Outcomes