AD7124-8 How do I interface to multiple ADCs over the same serial interface?
A single microcontroller can be used to communicate with several AD7124-8
devices. The input of the ADC can be used to enable or disable the serial
interface of the ADC. By controlling the 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 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 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
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
Interfacing several ADCs to a single microcontroller.