ADS131B04-Q1: EFT test, ADC output abnormal data

Colin Chen

Part Number: ADS131B04-Q1

Tool/software:

Dear Experts,

We have discussed a similar issue beforeADS131B04-Q1: ADC output data is inaccurate - Data converters forum - Data converters - TI E2E support forums. Currently, my customer is experiencing abnormal A1 channel sampling output data during EFT pulse testing; Even when there is no input at the A1 input terminal, the sampled output will still read a voltage output of approximately 956mV. This phenomenon is very strange, and even if the /DRDY pin is pulled up, it cannot be eliminated; At present, we suspect that EFT testing may clamp the internal input to a specific voltage. We would like to ask if TI has encountered any output abnormalities during similar testing for other customers, and what the possible reasons for such abnormalities may be. We hope to receive an answer. Thank you

23 days ago

0 Dale Li 23 days ago

TI__Mastermind 45685 points

Hi Collin,

EMC tests including EFT are system level tests and the test result is highly related to the system design including proper protection circuity, layer stackup, proper grounding, shielding, filtering, and careful PCB design and so on. The unwanted interference signals can be coupled into analog input through signal trace, ground or it can be radio frequency (RF) interference, the digital signals can be also affected by those interference signals. If only one channel is affected, the most likely reason is the PCB layout design issue. To address it, you can monitor the analog input on the affected channel, and also the whole design files including schematic and PCB layout are needed for review. I would be happy to do that and provide my suggestion if you could share them.

BR,

Dale