Some new PIC 33E and 24E microcontrollers can take simultaneous samples from multiple analog to digital converters. Most chips measure analog values sequentially, but this ADC can sample 4 signals at once. Samples are still converted one after the other, but they’re collected at the same moment. More in the reference manual for dsPic33E and PIC24E 16bit devices:
This document describes the features and associated operational modes of one of the successive approximation (SAR) Analog-to-Digital Converter (ADC) modules available on the dsPIC33E/PIC24E families of devices. This ADC module can be configured by the user application to function as a 10-bit, 4-channel ADC or a 12-bit, single-channel ADC. On devices with DMA, this ADC module can be configured to use DMA or use a dedicated 16-word memory mapped buffer instead of DMA.