Q. How do I interface to multiple ADCs over the same serial interface?
A. A single microcontroller can be used to communicate with several AD7124-8 devices. The /CS input of the ADC can be used to enable or disable the serial interface of the ADC. By controlling the /CS inputs to the ADCs using a decoder, the microcontroller can communicate with each ADC individually or simultaneously. The figure below shows the interface between a microprocessor and several ADCs. The /CS input of each ADC is connected to the decoder. Using the decoder, the microprocessor can select the ADC with which it wants to transfer data/instructions. When /CS is high, the serial interface of the ADC is disabled and it ignores any activity on the data bus. To communicate with the ADC, its /CS line can be taken low. The ADC will then have access to the data bus between itself and the microprocessor. The datasheet should be consulted for timing specifications.
Interfacing several ADCs to a single microcontroller.