Conclusion

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Conclusion

This application note illustrates how designers can diagnose the state of two AC switches

with only one single microcontroller ADC input. The way to implement this solution in the

application and the external resistor choice is described in this document.

This solution is used to detect the failure modes of two AC switches and to inform the MCU

so that appropriate actions to put the system into a safe state can be taken. This function

improves the system safety by detecting "diode mode" in both polarities of the AC mains,

"short circuit" and "open circuit" of each AC switch independently.

The main benefit of this solution is to reduce the cost of the microcontroller when a platform

needs to monitor several AC switches because it requires one less pin.