I am having trouble interpreting the Output Data Section of the datasheet for the ADS62P22 ADC.

Page 56 includes the following description:

Output Data Format

Two output data formats are supported - 2s complement and straight binary. They can be selected using the serial interface register bit DATA FORMAT or controlling the SEN pin in parallel configuration mode.

In the event of an input voltage overdrive, the digital outputs go to the appropriate full-scale level. For a positive overdrive, the output code is 0x7FF in offset binary output format, and 0x3FF in the 2s complement output format. For a negative input overdrive, the output code is 0x000 in offset binary output format and 0x400 in the 2s complement output format.

(emphasis mine)

Based on this description, the full code range for the straight binary output format is 0x000 to 0x7FF or 0 to 2047 in decimal. The full code range for the 2s complement format is 0x400 to 0x3FF, or -1024 to 1023 in decimal. Both of these ranges have a total of 2048 codes, which only requires 11 bits.

But this is a 12 bit ADC. What happened to the other half of the codes?

  • 2
    \$\begingroup\$ Most likely it's just an error in the datsheet. You could ask on the TI website ("MyTI" forums, I think) and probably get a response from a TI apps engineer. \$\endgroup\$
    – The Photon
    Apr 26, 2019 at 16:48
  • \$\begingroup\$ I suspected a datasheet error, but wanted to get some more eyes on it to make sure I wasn't overlooking anything obvious \$\endgroup\$ Apr 26, 2019 at 16:55

1 Answer 1


Update: I reached out to TI, and they confirmed that this is an error with their datasheet.



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