Power supply apparatus and image forming apparatus

An image forming apparatus, comprising:

• a transfer unit configured to transfer a toner image onto a sheet;
• and
• a fixing unit configured to fix the toner image transferred onto the sheet by the transfer unit, on the sheet by heat of a heater,
• wherein the fixing unit includes:
• a first circuit connected to a predetermined power supply;
• a second circuit insulated from the first circuit;
• a switcher provided in the first circuit and configured to switch between a supplied state where power is supplied from the predetermined power supply to the heater, and an interrupted state where the power is not supplied from the predetermined power supply to the heater;
• a driver provided in the second circuit and configured to output a switching signal to switch a state of the switcher;
• an adjusting unit provided in the first circuit and configured to adjust the power supplied from the predetermined power supply to the heater;
• a first control unit provided in the first circuit and configured to detect a parameter relating to the power supplied to the heater;
• a second control unit provided in the second circuit and configured to control the adjusting unit;
• a first communication portion provided in the first circuit and connected to the first control unit;
• and
• a second communication portion provided in the second circuit, insulated from the first communication unit, and is configured to perform wireless communication with the first communication portion,
• wherein the first control unit is operated by power that is supplied upon receiving a signal generated in the first communication portion due to a signal provided from the second control unit to the second communication portion,
• wherein the first control unit transmits, to the second communication portion, information about a detection result,
• wherein the second control unit controls the adjusting unit based on the information transmitted to the second communication portion,
• wherein the first control unit outputs, to the driver, a predetermined signal for causing the driver to output the switching signal for putting the switcher into the interrupted state in a case where abnormality occurs in the second circuit, and
• wherein the driver outputs the switching signal for putting the switcher into the interrupted state when the predetermined signal is output from the first control unit.