JAJSFU8D November 2017 – June 2024 ADS8166 , ADS8167 , ADS8168
PRODUCTION DATA
In manual mode, the channel ID of the desired analog input is configured in the CHANNEL_ID register. On power-up or after device reset, AIN0 is selected and CHANNEL_ID[2:0] = 000b. Enable manual mode from any other sequencing mode by programming the SEQ_MODE[1:0] bits to 00b in the DEVICE_CFG register. Figure 6-12 shows the timing information for changing channels in manual mode.
Update the channel information in a microcontroller (MCU)-friendly 3-byte access. Because the 24 bits of channel configuration are sent over SDI, conversion data are clocked out over SDO. The data on SDO are MSB aligned and the first 16 clocks correspond to 16 bits of conversion data. The last eight bits of the SDO are ignored by the MCU.
As shown in Figure 6-12, the command to switch to AINy is sent in the Nth cycle and the data corresponding to channel AINy is available in the (N + 2)th cycle. This switch occurs because the SDI commands are processed and the ADC starts conversions on the rising edge of CS. Thus, the conversion is processed on the previous channel (AINx) and not on the updated channel ID (AINy).