Part Number: TMS320F28377D
Hi all,
My customer is facing ADC problem and the configurations are as follows,
ADC-A, 16-bit resolution, differential input, VREFHIA = 2.5V, VREFLOA = 0V.
ADCINA2 : DC_IN_P
ADCINA3 : DC_IN_N
ADC-C, 16-bit resolution, differential input, VREFHIC = 2.5V, VREFLOC = 0V.
ADCINC14 : SIN_IN
ADCINC15 : 1.25V DC
ADC-D, 16-bit resolution, differential input, VREFHID = 2.5V, VREFLOD = 0V.
ADCIND0 : COS_IN
ADCIND1 : 1.25V DC
The SIN_IN and COS_IN are from incremental encoders of HIPERFACE motor. When motor is stationary, ADC-A gets correct conversion data of DC voltage input and gets wrong results when motor is spinning. The faster motor speed, the greater error of ADC-A results.
We monitor the DC voltage input and the ADC reference voltage, all the voltages look good when motor is spinning, we have no idea the reason ADC-A gets wrong results when there are signals connected to ADC-C and ADC-D.
What should we do for further investigation? Please advise your idea, thanks for help.
Regards,
Luke
