ZHCSJX5 June 2019 ADS7028
ADVANCE INFORMATION for pre-production products; subject to change without notice.
The ADS7028 features a built-in oversampling (OSR) function that can be used to average several samples. The averaging filter can be enabled by programming the OSR[2:0] bits in the OSR_CFG register. The averaging filter configuration is common to all analog input channels. Figure 5 shows that the averaging filter module output is 16 bits long. In manual conversion mode and auto-sequence mode, only the first conversion for the selected analog input channel must be initiated by the host; see the Manual Mode and Auto-Sequence Mode sections. As shown in Figure 5, any remaining conversions for the selected averaging factor are generated internally. The time required to complete the averaging operation is determined by the sampling speed and number of samples to be averaged. As shown in Figure 5, the 16-bit result can be read out after the averaging operation completes.
In autonomous mode of operation, samples from analog input channels that are enabled in the AUTO_SEQ_CH_SEL register are averaged sequentially. The digital window comparator compares the top 12 bits of the 16-bit average result with the thresholds.
Equation 2 provides the LSB value of the 16-bit average result.