Rohm Co., Ltd.

Rohn Co., Ltd.

Yoshihiro Ikefuji

Shigemi Chimura

Junichi Hikita

Hiroharu Okada

Haruo Taguchi

Hiroo Mochida

Hideki Hayashi

Takayuki Nakashima

Akihiro Okui

Toyokazu Komuro

Satoshi Yoshioka

Masahide Tanaka

Sadakazu Murakami

Takashi Ueda

Mitsuhiko Noda

Nobuyuki Yamada

Kimitake Utsunomiya

Yusuke Yoshii

Shozo Miyagawa

Mitsuro Saji

Takeshi Seike

Mitsuru Koiwa

Junya Sato

This power transmission apparatus transmits power to a power reception apparatus by means of a magnetic field resonance system by supplying an output AC voltage (V) of a class E amplifier to a power-transmission side resonance circuit (TT). Before the transmission of power, the output AC voltage (V) of the class E amplifier is divided, and a voltage obtained by the division is supplied to the power-transmission side resonance circuit (TT). A current amplitude detection value of a power-transmission side coil (T) at this time is obtained as an evaluation value, and whether to permit execution of power transmission is controlled on the basis of the evaluation value, through determination as to whether a foreign object is present or not.

Power transmission device and non-contact power feeding system for transmitting electric power to power reception device by magnetic resonance

In a non-contact power feeding system which is formed with a power transmission device having a power transmission-side resonant circuit including a power transmission-side coil and a power reception device having a power reception-side resonant circuit including a power reception-side coil and which can transmit and receive power by a magnetic field resonance method, when the power is transmitted, the power transmission device monitors the amplitude of a current flowing through the power transmission-side coil. Then, when a current amplitude detection value (V) falls outside a predetermined normal range, it is determined that a foreign object is present, and thus the power transmission is stopped.

Power transmission device non-contact power feeding system with detection circuit to detect current amplitude in transmission-side coil

In this non-contact power feeding system that is capable of transmitting power from a power transmitting device () to a power receiving device () by a magnetic field resonance scheme, the power transmitting device () is provided with first to n-th resonant circuits (TT[]-TT[n]) which are provided with coils (T) that are different in size, respectively, and which have a resonant frequency set to a prescribed reference frequency. Prior to power transmission, test magnetic fields are generated in sequence in the first to n-th resonant circuits to detect the amplitude of current flowing through the coils of respective resonant circuits, and the presence/absence of a foreign object is determined on the basis of the obtained first to n-th amplitude detected values, to control execution of the power transmission.

Power transmitting device and non-contact power feeding system

In a normal mode, a power receiving device changes the resonant frequency of a power receiving side resonant circuit from a reference frequency or short-circuits a power receiving side coil for a predetermined time and then eliminates the changed or short-circuited state. Meanwhile, in the normal mode, a power transmitting device generates a test magnetic field in a power transmitting side coil during the above changed or short-circuited period and then determines, on the basis of a current amplitude detection value of the power transmitting side coil, whether a foreign object is present or not, thereby determining and controlling whether power transmission is executed or not. In a test mode, the power receiving device maintains the above changed or short-circuited state, and the power transmitting device continuously generates the test magnetic field and continuously obtains the current amplitude detection value of the power transmitting side coil.

Non-contact power feeding system

A power reception device includes a power reception-side resonant circuit which includes a power reception-side coil and a metal plate in which an opening portion is provided in a position opposite the arrangement position of the power reception-side coil, and can receive, by a magnetic field resonance method, power from a power transmission device which includes a power transmission-side resonant circuit including a power transmission-side coil. A cancellation coil is arranged between the power reception-side coil and the opening portion, and a cancellation resonant circuit including a cancellation coil is provided separately in the power reception device. When an alternating magnetic field interlinks the cancellation coil, a current which cancels out variations in the resonant frequencies of the power reception-side resonant circuit and the power transmission-side resonant circuit caused by the presence of the metal plate flows through the cancellation coil.

Power reception device and non-contact power feeding system

A non-contact power supply system includes a power transmission device including a first resonance circuit having a first coil for transmitting electric power; and a power reception device including a second resonance circuit having a second coil for receiving the electric power. The system is configured to transmit and receive the electric power by a magnetic field resonance method, and to communicate between the power transmission device and the power reception device. The power transmission device includes a power transmission circuit for supplying an AC voltage to the first resonance circuit; a detection circuit configured to detect an amplitude of a current flowing through the first coil; and a control circuit configured to control the power transmission circuit to perform power transmission control of the electric power.

Non-contact power supply system and power transmission device

Disclosed is a non-contact power supply system wherein power is transmitted by means of a magnetic field resonance method from a power transmission device, which includes a power transmission-side resonant circuit, to a power reception device, which includes a power reception-side resonant circuit. The power transmission device detects, at the time of transmitting the power, a load in the power transmission, and stops the power transmission in the cases where a detection result deviates from a specified normal range. In the power reception device, a power stabilization circuit () that maintains output power of the power reception circuit constant is provided between a load circuit () and a power reception circuit () that outputs, toward the load circuit, power on the basis of power received by the power reception-side resonant circuit.

Non-contact power supply system

In a non-contact power feeding system which is formed with a power transmission device that includes a power transmission-side resonant circuit including a power transmission-side coil and a power reception device that includes a power reception-side resonant circuit including a power reception-side coil and which can transmit and receive power by a magnetic field resonance method, the control circuit of the power transmission device supplies, before the power transmission, a predetermined determination alternating current voltage to the power transmission-side resonant circuit so as to detect the amplitude of a current flowing through the power transmission-side coil at that time. The control circuit controls the performance of the power transmission based on the current amplitude detection value.

Power transmission device and non-contact power feeding system

Provided is a charging system characterized by being provided with: a mobile device including a first NFC antenna and a rechargeable battery which is charged on the basis of a current induced in the first NFC antenna by electromagnetic induction; and a charger including a second NFC antenna which causes electromagnetic induction to be induced in the first NFC antenna, and a supply unit which supplies the second NFC antenna with a feed current for inducing the electromagnetic induction; and in that the charging system is further provided with a control means for causing an intended electromagnetic induction to arise between the first NFC antenna and the second NFC antenna.

Charging system using NFC, mobile device chargeable by NFC, and charger

A power reception apparatus includes a power receiving circuit to be connected to a power reception side resonance circuit including a power reception side coil and a power reception side capacitance, for generating an output power based on power received by the power reception side coil utilizing magnetic resonance, a changing/short-circuiting circuit configured to change a resonance frequency of the power reception side resonance circuit from a reference frequency that is the resonance frequency when receiving the power, or to short-circuit the power reception side coil, before receiving the power.

Power reception apparatus, power transmission apparatus, non-contact power supply system, power reception method, and power transmission method

A personal identification device has: a light source portion that emits infrared light with a first wavelength at the time of reading a vein pattern, and emits infrared light with a second wavelength longer than the first wavelength at the time of reading a fingerprint pattern; a light receiving sensor portion that detects a component of the infrared light reflected from a fingertip after being shone thereon from the light source portion; an amplifying portion that amplifies a detection signal obtained by the light receiving sensor portion; an A/D converting portion that converts an analog signal obtained by the amplifying portion into a digital signal; a data distributing portion that distributes the digital signal obtained by the A/D converting portion into two groups of data, of which one is vein pattern data and the other is fingerprint pattern data; and a processing portion that verifies the identity of a person based on the vein pattern data and the fingerprint pattern data distributed by the data distributing portion.

Personal identification device and electronic apparatus provided therewith

A filter circuit has: a first and a second current mirror circuit that are each built with a plurality of transistors and that respectively pass a first and a second mirror current according to a constant current; an input terminal via which an input pulse signal is fed in; a first transistor that, in response to the signal fed in via the input terminal and by using a supply voltage, makes the first current mirror circuit operate; a second transistor that, operating in inverted synchronism with the first transistor, in response to the signal fed in via the input terminal and by using a ground voltage, makes the second current mirror circuit operate; a capacitor that is charged by the first mirror current and that is discharged by the second mirror current; and an output terminal via which a voltage at one end of the capacitor is fed out. Thus, the filter circuit permits its filter constant to be set accurately in a wide range without relying on the driving capacity of the input signal, and can be integrated without an undue increase in device scale.

Filter circuit, and image sensor, image sensor module, and image reading apparatus provided therewith

There is provided a liquid crystal display device including a first transparent substrate and a second transparent substrate pasted to each other via a liquid crystal sealing space in between, and provided with a predetermined display region. The first transparent substrate is integrally formed with an extension extending further than an edge of the second transparent substrate and longitudinally of the edge of the second transparent substrate. The extension is provided with at least one semiconductor chip having a longitudinal axis laid longitudinally of the extension. The extension is formed with an external connection terminal region including a plurality of terminals. The external connection terminal region does not overlap the semiconductor chip widthwise of the extension.

Method of making semiconductor chips for liquid crystal display device

In an IC cardis sealed an IC chipprovided with an exposure sensor. When exposure sensordetects that IC cardhas been opened, exposure sensoroutputs an exposure detection signal to a CPU. In response to the exposure detection signal, CPUprovides a predetermined operation, such as erasure of data in a non-volatile memory. As such, the data in non-volatile memorycannot be obtained if IC cardis improperly opened to check the data in non-volatile memory. Thus the IC card can obtain an enhanced data security.

IC card and IC chip module

Upon receiving an encipherment command, an enciphered authentication data generation circuit generates an enciphered authentication data based on a basic authentication data including a random number portion using an encipherment rule. The encipherment rule changes according to the number of supplied encipherment commands. A transmission circuittransmits the enciphered authentication data. A reception circuitreceives the enciphered authentication data transmitted from a second deviceA prohibition command output circuitdetermines whether the enciphered authentication data transmitted from the second devicematches with an enciphered authentication data that would be generated if the same number of encipherment commands were supplied to an enciphered authentication data generation circuit of a first deviceand outputs a prohibition command to prohibit a transmission of the data to be transmitted when the determination result is negative.

Growing community of inventors

Kyoto, Japan

Yoshihiro Ikefuji