I am using LTC2497. I am trying to get the ADC conversion reading, could anyone explain how does the conversion of 2's compliment to decimal works on this ADC? I tried many times and it does not seem to be working.
Thanks for the promopt response. I tried the conversion...I still didnt get the result..did i missed anything?
After the conversion, it is necessary to send the read address which the LTC2497 should ACK and then read out the data. It sounds like the ADC is not acknowledging the read address you are providing. Can…
The LTC2497 is 16 Bits + Sign. B22-B6 are in two's complement format. For example Code 1010 0000 0000 0000 0000 0000
B23 and B22 are 10. This indicates the output code is greater than or equal to 0 and less than full scale . Bits 22-6 are 0 1000 0000 0000 0000. This is equal to decimal +32768.
A negative code example would be 0111 1111 1111 1111 1111 1111. B23 and B22 are 01. This indicates the output code is less than 0 and reater than or equal to -FS. Bits 22-6 are 1 1111 1111 1111 1111. this is equal to decimal -1.
what is your reference voltage? Are you doing single-ended or differential measurement? Is the -input at ground or at vref/2? Decoding the input voltage of 0.507, assuming a 5V reference and the -input grounded, I come up with 0.5407V. That is in the ballpark. Remember +FS is only Vref/2. Can you provide a schematic or give more details? you might have a filter settling issue to account for the rest of the error.