SURGERY ASSISTANCE DEVICE

A surgery assistance device includes a battery, loads, a manual switch, a power supply, and a backup power supply. The power supply is connected to a mains power supply and to the loads, and outputs a first power supply voltage to the loads. The manual switch is connected to a portion of the loads. The backup power supply is connected to the battery and to the manual switch, and outputs a second power supply voltage to the portion of the loads when the manual switch is closed.