Q. I am not designing a system for functional safety. Are the diagnostics in AD7124-8 still useful?
A. The on-chip diagnostics are useful in any system, even an application where functional safety is not important. The on-chip diagnostics allow the user to verify the circuit connections, the blocks within the ADC such as the PGA, reference and ADC itself can be monitored to ensure that all blocks are functioning correctly. Since the on-chip registers can be monitored, the user can be confident that no register changes have occurred. Finally, the serial interface has a lot of diagnostics such as read/write checks, any invalid read/write operations are ignored.
On other ADCs, the ADC does not ignore invalid commands which can lead to register corruption or even the serial interface becoming asynchronous. The AD7124-8’s diagnostics give the user confidence that only correct read/write operations are sent/received by the AD7124-8, that on-chip registers are not corrupted, and that conversions are invalid. Any errors for these conditions will be indicated by the Error bits.