Sony Corporation

Saturn Licensing LLC

Yoshiki Oyama

Noburo Ogura

Nobuhiko Kanoi

Yasushi Katayama

Tatsuki Nishino

Mitsuru Yamane

Makoto Kobori

Masanobu Takahama

A synchronous rectification control circuit includes a first drive unit that outputs a signal for controlling turning on/off of a synchronous rectification element disposed on a secondary side, a second drive unit that performs control to make a voltage between both ends of the synchronous rectification element equal to a predetermined threshold voltage during a predetermined period during which a rectification current flows on the secondary side, and a drive switching unit that selectively supplies an output from the first drive unit and an output from the second drive unit to the synchronous rectification element.

Synchronous rectification control circuit, control method, power supply system, electronic apparatus, electric vehicle, and electric power system

A liquid crystal display apparatus is capable of reducing a power loss incurred by a power-supply section in a process of generating a power-supply voltage for driving a backlight section. In the configuration of the power-supply section, a main power-supply circuit and an inverter circuit (or a DC-DC converter) are connected to an input-voltage generation unit in parallel to each other, which is used for rectifying and smoothing the commercial alternative current power. The main power-supply circuit and the inverter circuit (or the DC-DC converter) each include an isolation transformer including a primary-side winding not isolated from the commercial alternative current power and a secondary winding provided on the secondary side. The direct current input voltage is supplied to the primary side to be subjected to a power conversion process to generate an output voltage on the secondary side of the isolation transformer. Thus, the number of power conversion process stages for supplying power to the backlight section connected to the inverter circuit (or the DC-DC converter) is reduced by 1. As a result, the power loss incurred by the power-supply section can be reduced to a value smaller than that of the conventional one.

Power-supply apparatus and display apparatus

Power supply apparatus and display apparatus

A light emitting element drive device includes: a light emitting section having a light emitting element; output capacitance capable of storing power supplied to the light emitting section; a driver connected between the light emitting section and a reference potential and including a switch section whose conductive state is controlled by a pulse-like lighting signal depending on magnitude of a load current and a constant current source section connected in series to the switch section; and a power supply controller being a power supply that provides drive power to the light emitting section and including a function to adjust an output current supplied to the output capacitance. The power supply controller changes the supply amount of the output current for the light emitting section from the power supply controller based on load current information that is necessary peak power of the light emitting section.

Light emitting element drive device, light emitting element drive method, and display apparatus

A light emitting diode driving apparatus includes: a switching converter having an inductor and a switching device; a plurality of serial light emitting diode lines each having a plurality of light emitting diodes connected in series; a plurality of rectifier diodes respectively connected in series to the plurality of serial light emitting diode lines; a plurality of capacitors respectively connected to nodes between the serial light emitting diode lines and the rectifier diodes for smoothing a voltage; and one or more current distribution coils disposed between the switching converter and the plurality of serial light emitting diode lines to let a current flow in a direction of canceling out a magnetic flux generated by a first winding and a magnetic flux generated by a second winding each other, thereby making currents flowing in the serial light emitting diode lines equal to each other.

Light emitting diode driving apparatus

A light emitting diode (LED) driving apparatus includes a drive section for driving an LED to emit light, and a control section that controls a driving current supplied from the drive section to the LED. The control section implements luminous power control by controlling an ON/OFF ratio of the driving current if a target value of luminous power of the LED is smaller than a predetermined value. The control section implements luminous power control by controlling a level of the driving current if the target value is equal to or larger than the predetermined value.

LED driving apparatus and method of controlling luminous power

In order to suppress leak current at the time of high voltage application to a fluorescent lamp so as to improve the luminous efficiency, the present invention provides a fluorescent lamp driver, which includes switching means that switches a DC power supply voltage, and a first transformer and a second transformer configured to obtain AC voltages each having reverse polarity, as AC voltages excited from primary winding to secondary winding of the respective transformers, on the basis of output voltages of the switching means, in which the first transformer and the second transformer are positioned in the vicinity of both ends of the fluorescent lamp, and the AC voltage obtained in the secondary winding of the first transformer is applied to one terminal of the fluorescent lamp and the AC voltage obtained in the secondary winding of the second transformer is applied to the other terminal of the fluorescent lamp.

Fluorescent lamp driver and liquid crystal display apparatus

A light emitting element drive circuit and a display system able to simultaneously perform constant current control and PWM control and able to perform a stable adjustment of luminance over a wide dynamic range, including a constant voltage source having an output voltage adjustment unit able to be changed in output voltage according to a signal from the outside, a switch circuit connected to the cathode side of the LED and ON/OFF controlled in accordance with a PWM signal from the outside, a current detection unit for detecting the current flowing in the circuit, and a sample and hold circuit for maintaining the current input value from the current detection unit for a constant period, and the output voltage adjustment unit receives as input the output of the sample and hold circuit, that is, the current value when the switch circuit is ON, and adjusts the output of the constant voltage source so that this value becomes a previously determined set value, to thereby make the current flowing in the LED constant.

Light emitting element drive device and display apparatus

A discharge tube lighting apparatus is used to drive a plurality of discharge tubes. The apparatus includes a balance coil having a winding input end and a plurality of winding output ends to which the discharge tubes are connected individually; a power section for supplying ac current to the winding input end of the balance coil; and a control section for detecting a peak value of detection voltages corresponding to voltages at the winding output ends of the balance coil and for stopping the supply of the ac current from the power section when the peak value of the detection voltages is higher than a predetermined value.

Discharge tube lighting apparatus, light source apparatus, and display apparatus

An AC plug provided with a plug casing and prongs formed sticking out from the inside of the plug casing to the outside and supplying AC power supplied from a power outlet to the prongs by an AC cord connected to the prongs inside the plug when the prongs are inserted into the power outlet, further provided with, inside the plug casing in series between the prongs, a discharge resistor for discharging a residual charge across the prongs when the prongs are pulled out from the power outlet and a switch turning off when the prongs are inserted into the power outlet, turning on when they are pulled out from the power outlet to pass the residual charge of one prong of the prongs to the other prong through the discharge resistor.

Growing community of inventors

Kanagawa, Japan

Yoshiki Oyama