AD7790 reference voltage ripple

Hi,

May I know the output temperature readings? Also, can you provide your schematic together with the register map settings.

You may refer to Thermistor-Based Temperature Sensing System—Part 1: Design Challenges and Circuit Configuration | Analog Devices and Thermistor-Based Temperature Sensing System—Part 2: System Optimization and Evaluation | Analog Devices as reference. Though, the article uses AD7124, you may use other sigma delta ADCs for the same application and use the article as reference. 

Best Regards,

Rod

Hi,

Thank you for your quick reply! Is there a way to show the measurement error in relation to the reference voltage ripple? Here is the schematic of one channel. We are using buffered single mode measurements. Gain is set to the default value. (0x10; 0x82)

Best regards

Hi,

Can you provide the input (both AINs and REFs) and the output readings of the ADC using a probe? 

May I also ask the purpose of each of the 1kO resistors on your schematic?

You can also try to use a fixed voltage as a substitute for your temperature sensor and test for the output results. See whether the temperature reading is still off by ~ 1K. Thank you.

Best Regards,

Rod