Image forming apparatus using technique for controlling power supply

摘要

An image forming apparatus that ensures high-quality power supply to an AFE (analog front-end) and reduces the amount of power consumed by the AFE in sleep mode. The AFE, which converts an analog signal into a digital signal, and another circuit different from the AFE are incorporated in an SOC (system-on-a-chip). A switch circuit switches power to the AFE between first DC power supply from a 5-V/3.3-V_LDO and second DC power from a 24-V/3.3-V_DC-DC converter. When the AFE is in use, the switch circuit is controlled such that the first DC power is supplied from the 5-V/3.3-V_LDO to the AFE, and when the AFE is not in use, the switch circuit is controlled such that the second DC power is supplied from the 24-V/3.3-V_DC-DC converter to the AFE.

主权项

1. An image forming apparatus comprising:
a conversion circuit configured to convert an analog signal into a digital signal; a first power supply configured to supply first DC power to said conversion circuit; and a second power supply configured to supply second DC power to said conversion circuit using a method different from a method used by said first power supply; an integrated circuit in which said conversion circuit and other circuits different from said conversion circuit are incorporated; a switching circuit configured to switch power to said conversion circuit between the first DC power and the second DC power; and a control unit configured to, when said conversion circuit is in use, control said switching circuit such that the first DC power is supplied from said first power supply to said conversion circuit, and when said conversion circuit is not in use, control said switching circuit such that the second DC power is supplied from said second power supply to said conversion circuit.