An information processing apparatus according to the present invention is operated by at least switching between a first power state and a second power state in which its power consumption is less than that of the first power state. In a case where an event detected during a period from start to end of processing of making transition from the first power state to the second power state is a communication establishment event, the information processing apparatus causes a communication unit to transmit to a communication partner a notification for maintaining connection of communication in the second power state.

A power control device receiving supply of power from a power source, the power control device including: a power accumulator accumulating a part of power from the power source; a first voltage converter receiving power from the power source and the power accumulator, performing voltage conversion to a first target voltage, and supplying power with the first target voltage to a first load; a second voltage converter receiving power from the first voltage converter, performing voltage conversion to a second target voltage, and supplying power with the second target voltage to a second load; a power source monitor monitoring power from the power source; and a power controller lowering the first target voltage to a level that the second voltage converter is capable of converting to the second target voltage when the power source monitor detects that the supply of power from the power source has stopped.

An image forming apparatus includes: a communication unit that receives first mode electric power to perform communication; an image forming unit that receives first mode electric power the to form an image on a medium; a fixing unit that generates heat by receiving first mode electric power corresponding, and performs a fixing process of fixing the image to the medium; a predicting unit that predicts a processing time required for a process of forming the image; and a supply controller that controls supply of electric power according to a first mode or a second mode in which power consumption is smaller than that of the first mode. The supply controller starts the supply of first mode electric power to the fixing unit at a timing based on the predicted processing time when the image forming apparatus transitions from the second mode to the first mode.

A control device is provided and includes: an acquisition unit that acquires the number of persons from a count unit, the count unit counting up the number of persons in an area based on a detection result of a first detection unit, the first detection unit detecting a person who goes in and out through an entrance of the area; and an operation mode control unit that controls an operation mode of a processing device according to the acquired number of persons.

An image forming system includes an image forming apparatus, an option device, and a power supply line. The image forming apparatus includes an apparatus controller, an image forming unit, and an apparatus power supply. The apparatus power supply is configured to generate a control voltage that is supplied to the apparatus controller and an apparatus drive voltage that is supplied to the image forming unit. The option device includes a drive load, an option power supply, an option controller, and a detector. The option controller is configured to control the option power supply and receive the control voltage supplied from the apparatus power supply, via the power supply line. The detector is configured to transmit a detection signal to the option controller, the detection signal from among a plurality of different detection signals corresponding to operation statuses of the option power supply.

A printing apparatus connectable to an external power supply having a plurality of outputtable electric power information, including: a printing head performing printing by electric power supplied from the external power supply; and a controller configured to: obtain the plurality of electric power information; determine whether the printing can be performed if electric power indicated by the obtained electric power information is supplied from the external power supply; decide, as request electric power information, any one of the electric power information indicating possible electric powers; request the external power supply to output electric power indicated by the request electric power information; calculate a print control value for controlling the printing head based on the decided request electric power information; and control the printing head to perform the printing based on the calculated print control value.

The power supply apparatus includes a control unit configured to output a pulse signal for driving a switching element, to drive a transformer to output a voltage from a secondary winding of the transformer, and a memory unit configured to store information associating the output voltage with the duty and the frequency of the pulse signal, and the control unit switches the frequency and the duty based on the output voltage and the information stored in the memory unit.

A printing apparatus connectable to an external power supply having a plurality of outputtable electric power information, including: a printing head performing printing by electric power supplied from the external power supply; and a controller configured to: obtain the plurality of electric power information; determine whether the printing can be performed if electric power indicated by the obtained electric power information is supplied from the external power supply; decide, as request electric power information, any one of the electric power information indicating possible electric powers; request the external power supply to output electric power indicated by the request electric power information; calculate a print control value for controlling the printing head based on the decided request electric power information; and control the printing head to perform the printing based on the calculated print control value.

An image processing apparatus includes a fluctuation generating portion, and a connection identifying portion. The fluctuation generating portion fluctuates an output power of a power supply portion that supplies power to a load. The connection identifying portion identifies a connection relationship between the power supply portion and the load based on a correlative relationship between a fluctuation of the output power and a fluctuation of the power supplied to the load.

There is provided an image reading apparatus in which a low output mode is a mode that can be controlled in a coupling state where a low power-feeding USB device is coupled, a high output mode is a mode that can be controlled in a coupling state where a high power-feeding USB device capable of feeding power higher than the low power-feeding USB device is coupled, and a control section does not perform image reading at a second reading speed faster than a first reading speed and performs image reading at the first reading speed in the low output mode.