USB (universal serial bus) and ADC (analog to digital converter) interface multiplex circuit and multiplex method

The invention relates to a multiplex circuit, particularly to a USB (universal serial bus) and ADC (analog to digital converter) interface multiplex circuit and a multiplex method. The USB and ADC interface multiplex circuit comprises external pins, a multiplex control circuit, a USB module and an ADC module. The external pin 1, the multiplex control circuit and the USB module are sequentially electrically connected. The external pin 2, the multiplex control circuit and the ADC module are sequentially electrically connected. The USB and ADC interface multiplex circuit is unique in structure and allows the circuit to control signals from the inside, in this way, the chip interface works in the time sharing manner under the USB mode and the ADC mode, so that interface kinds of the processor chip or system on chip are enriched, and fewer universal pins of the chip are required.