an event-detection circuit, detecting a sudden event, and correspondingly outputting an interrupt notification and a protection-enable signal according to the sudden event;

a protection-control circuit, receiving the protection-enable signal, and correspondingly outputting a protection-execution signal;

a digital-to-analog converter;

a digital-to-analog conversion interface controller, receiving the protection-execution signal, stopping an update of received input data, stopping an output of an acknowledgement signal, and enabling the digital-to-analog converter to suspend a signal conversion;

a trigger-event controller, determining whether to set conversion parameters of the digital-to-analog conversion interface controller according to the acknowledgement signal; and

a central processing unit, determining the conversion parameters, outputting the conversion parameters to the trigger-event controller, and receiving the interrupt notification to eliminate the sudden event.