US Patent 7761017 Power supply apparatus and image forming apparatus

A power supply apparatus includes an error detecting unit configured to perform error detection to detect that an output node and another node are placed in a short-circuit state or open-circuit state, a condition change detecting unit configured to detect a change in an external condition, and an operating-point changing unit configured to change an operating point of the error detection performed by the error detecting unit in response to the change detected by the condition change detecting unit.