SWRU626 December 2025 CC3501E , CC3551E
In AUTO mode, the sample signal is generated synchronous to the sampling clock (SAMPCLK) and can be programmed using an internal sampling timer to determine the duration of the sampling window. The sample timer is 10-bit wide and there are two sample time compare registers (SCOMPx) available to account for various source impedances to measure signals from. One of these two SCOMP registers can be selected using the STIME bit in the MEMCTL register.
Figure 24-2 shows the ADC sample and conversion timing diagram when the ADC is configured in AUTO sampling mode.
When the reset value of PWRDN is set as ‘0’, which has the default behavior of automatic power down, ADC wake-up time needs to be considered in each sample window. Refer to the device-specific data sheet for specifications on the ADC wake-up time. For example, if the maximum ADC wake-up time is 5 µs, then the duration set by SCOMPx is > (5 µS + Duration for sample window).