US Patent 10111679 Circuitry and sensors for powered medical device

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit, a supplementary power supply circuit configured to supply electrical power to a secondary circuit, and a sleep mode monitor coupled between the main power supply circuit and the supplementary power supply circuit. The sleep mode monitor is configured to indicate one or more sleep mode conditions. The electronic system further comprises a device state monitor coupled to the primary circuit, the device state monitor configured to sense a state of various electrical and mechanical subsystems of the surgical instrument.