Semiconductor Device Resolver Short-Circuit Detection

The patent applies preliminary action by performing short-circuit failure detection before the amplifier circuit operates with external input resistances. The detection circuit measures the potential at the external terminal when the amplifier is not yet connected to the resolver, thereby obtaining an accurate baseline potential without the influence of external resistances. This preliminary measurement enables subsequent gain adjustment while maintaining detection accuracy.

The patent introduces an intermediary detection circuit that measures the potential at the external terminal through a high-impedance buffer or voltage follower. This intermediary circuit allows the measurement of resolver potential without being affected by the input resistance value, as the buffer presents a very high input impedance that does not load the signal source. This enables accurate potential detection while maintaining the ability to use external input resistances for gain adjustment.

The patent applies universality by making the existing external terminal serve multiple functions: it acts as both the signal input terminal for the amplifier circuit and the detection point for short-circuit failure detection. By measuring the potential at this existing terminal through the intermediary detection circuit, the patent eliminates the need for a dedicated detection terminal, thereby maintaining detection accuracy without increasing the number of external terminals.

The patent introduces an intermediary detection circuit that enables the existing external terminal to function as a detection point without adding new terminals. The intermediary circuit taps into the potential at the existing terminal and processes it for failure detection, thereby achieving accurate short-circuit detection while maintaining the original terminal configuration and avoiding increased device complexity.

The patent applies periodic action by performing failure detection at specific intervals or at predetermined stages (such as during initialization or at regular maintenance intervals) rather than attempting continuous detection. The detection circuit periodically measures the potential at the external terminal to check for short-circuit failures, while the amplifier circuit operates continuously with external input resistances for gain adjustment. This periodic detection approach maintains both adaptability and reliability.

The patent applies preliminary action by performing failure detection before the amplifier circuit is activated or before external input resistances are connected. This preliminary detection ensures that any short-circuit failures are identified before they can affect the operation of the amplifier circuit, thereby maintaining both the adaptability of the amplifier configuration and the reliability of failure detection.