The power supply apparatus alternately repeats a control between a first control of varying a frequency of switching operation within a predetermined range and for a predetermined cycle according to a frequency determined based on a feedback voltage, and a second control of varying the frequency within a range narrower than the predetermined range or a third control of controlling the frequency to be a constant frequency.

An MFP 1 includes an image forming unit 4 which forms an image on a sheet S1, a USB interface 12 which is to be connected to a PC 101 via a USB and receives a preceding command described in accordance with a control transfer protocol that is a transfer scheme of USB connection, and a CPU 91 which executes a preparation operation of the image forming unit 4, in response to receiving the preceding command by the USB interface 12. The preceding command is described to instruct the preparation operation of the image forming unit 4.

The present disclosure provides a consumable chip, a consumable, an image-forming apparatus, a communication method, and a detection method. The consumable chip includes the first connection terminal, configured to be connected to the first connection pin when the consumable is installed on the image-forming apparatus; the second connection terminal, configured to be connected to the second connection pin when the consumable is installed on the image-forming apparatus; the power supply circuit, configured to convert the first input signal and the second input signal received through the first connection terminal and the second connection terminal into a DC voltage to supply power to the microcontroller; the demodulation circuit, configured to demodulate the first input signal and the second input signal to obtain demodulated signals; and the modulation circuit, configured to send modulation signals to the image-forming control unit through the first connection terminal and the second connection terminal.

According to one embodiment, there is provided a temperature abnormality detection circuit provided in a temperature control device includes a target temperature determination circuit, a difference arithmetic circuit, a temperature abnormality determination circuit, and a storage circuit. The temperature abnormality detection circuit is configured to determine the presence or absence of temperature abnormality by a response situation of a detected temperature by a temperature sensor, calculate a current temperature difference from the detected temperature acquired by the temperature sensor if it is determined that there is a temperature abnormality and an estimated WAE temperature value, and determine whether the temperature sensor is abnormal or the control circuit side is abnormal based on the result of comparison between the temperature difference and a preset threshold value.

An image forming apparatus includes an amorphous silicon photosensitive member, a developing device including a developer carrying member that carries a two-component developer, and a control portion. When a potential difference V0−Vdc between the photosensitive member and the developer carrying member has a first potential difference at which the toner is moved from the developer carrying member to the photosensitive member and a second potential difference at which the toner is moved from the photosensitive member to the developer carrying member, the control portion adjusts V0 or Vdc so that the first potential difference and the second potential difference are equal in value and opposite in polarity, and a first development current |Ia| that flows at the first potential difference and a second development current |Ib| that flows at the second potential difference satisfy 1.9×10.sup.−2≥|Ib|/N≥5.7×10.sup.3 [μA/mm].

A power supply apparatus including a switching element configured to supply or cut off electric power to a primary coil of a transformer by a switching operation, and a control unit configured to control the switching operation. The control unit is configured to perform intermittent control of repeating a switching period for performing the switching operation and a stop period for stopping the switching operation. In the switching period, when the control unit performs the switching operation a predetermined number of times, the switching period is transitioned to the stop period. In the stop period, when the control unit determines that a voltage output from a secondary coil of the transformer falls below a target voltage, the stop period is transitioned to the switching period. The control unit is configured to change the switching operation based on a length of the stop period.

A power supply apparatus generates an output voltage. A boost circuit boosts a voltage supplied from a reference voltage source and generates a first power supply voltage. A processor controls switching the boost circuit on and off. A first transistor is connected to the first power supply voltage. A second transistor is connected to a collector of the first transistor. A resistance element is connected to a collector of the second transistor. A voltage source is connected to the resistance element and generates a second power supply voltage. A collector voltage, which is an output voltage, of the second transistor is controlled by controlling an amount of base current of the first transistor.

An apparatus provided with a power source device indicating a converting unit includes a switching unit, a discriminating unit, and a controller. In the case where the discriminating unit discriminates that an overcurrent state occurs during an operation of the power source device in a first mode, the mode of the operation of the power source device is switched to a second mode by the switching unit and then the occurrence of the overcurrent state is notified.

The print head and light emitting elements, first and second drive circuits, and a control circuit. The light emitting elements and drive circuits are spaced from each other an arrangement pitch. The first drive circuit includes a first capacitor and sets a light emission level for the first light emitting element. The second drive circuit includes a second capacitor and sets a light emission level of the second light emitting element. The control circuit is connected to the first drive circuit by a first wiring and to the second drive circuit by a second wiring and controls voltages across the first and second capacitors individually. A difference between the length of the first wiring and the length of the second wiring is less than the arrangement pitch.

An electronic apparatus includes a first electronic device, a second electronic device, a bundled wire configured to supply at least one of an electric signal and electric power between the first and the second electronic devices, a frame member, a bundled wire guide, and a plurality of holding portions disposed at different positions on the wiring path. Each of the plurality of the holding portions includes a hinge portion connected to an upper portion of one of the pair of the side wall portions, a cover portion connected to the storage portion via the hinge portion, and an engagement portion to secure the cover portion in a closed position. The frame member includes a groove portion to which the bundled wire guide is fitted, and the bundled wire guide with the bundled wire stored is fitted into the groove portion.