Hi Sandeep, When both the AVDD and DVDD are applied to the ADS1220 , the ADC will take one conversion then power down. If you want to take another conversion you must send the START command. You can change the register settings to operate in continuous conversion mode and then issue the START command to start the conversions. It is hard for me to decipher your connections based on the information you gave me. There is a bridge application circuit shown on page 56 of the ADS1220 datasheet in section 9.2.3. This diagram demonstrates one possibility for how the connections could be made. It is also unclear as to how you are sourcing the AVDD and DVDD supplies. If voltages are generated from two separate sources there could be a large potential difference between them, and so the grounds should be connected together with respect to AVSS of the ADS1220 and DGND of the ADS1220 . This may be a reason why your device is getting hot. If AVDD is 5V, then you can use the 5V also for excitation. You must also make sure that the excitation ground and AVSS are at the same potential (connected together). If you have exceeded one of the absolute maximum ratings, it is possible that you have damaged the ADS1220 . Your device should not get hot. If it does, then you have an improper connection somewhere. As to the registers settings, they may or may not be correct. It shows by register settings that you are connecting the reference to the REF0 input pair. REFN0 must be connected to AVSS if that is the way you have your device connected. A complete schematic would be helpful instead of a description. You can take the Olimex schematic and draw your connections on it. Then send me a picture of your drawing if that makes it easier. Best regards, Bob B
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