There are two ways, one is to use two AD conversion chips, one for each of the two analog quantities. The two AD chips are controlled by the single chip microcomputer to start the conversion at the same time, so that the two analog values can be collected at the same time.
Another way is to use two sample holders (LF398) to temporarily save the instantaneous value of the analog. The two keeper are followed by an analog multiplexer followed by an analog multiplexer followed by an AD converter. The process is such that a hold signal is given to the two sample holders before acquisition, followed by selection of the multiplexer channel, followed by activation of the AD converter. Select the two channels of the multiplexer to obtain the values of the two analog quantities.