SBAS590E March 2016 – June 2020 ADS131A02 , ADS131A04
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
The ADC conversion data word is set to a 16-bit format with either of two conditions. First, if the M1 pin input is left floating, the device word format is set to a 16-bit word length. This sets the ADC output data length to 16-bits. Second, if the M1 pin input is set to GND and the M2 pin is set to IOVDD, the device word format is set to a 24-bit word length. In this second condition, the first 16 bits are used for the ADC data, while the last eight bits are used for the Hamming code. The 16 bits of data per channel are sent in binary two's complement format, MSB first. The size of one code (LSB) is calculated using Equation 8:
A positive full-scale input [VIN ≥ (FS – 1 LSB) = (VREF / Gain – 1 LSB)] produces an output code of 7FFFh and a negative full-scale input (VIN ≤ –FS = –VREF / Gain) produces an output code of 8000h. The output clips at these codes for signals that exceed full-scale.
Table 8 summarizes the ideal output codes for different input signals.
INPUT SIGNAL, VIN
VAINxP - VAINxN |
IDEAL OUTPUT CODE(1) |
---|---|
≥ FS (215 – 1) / 215 | 7FFFh |
FS / 215 | 0001h |
0 | 0000h |
–FS / 215 | FFFFh |
≤ –FS | 8000h |