Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Tadata Hatanaka

Jun-ichiro Hara

Takuya Ishii

Atsushi Kitagawa

Takuya Tomida

Shigeo Masai

A DC-DC converter module includes a module substrate on which switching transistors and a controller IC chip are mounted, stud terminals mounted on a surface of the module substrate, and an inductor attached to the stud terminals such that the inductor faces the module substrate. In a plan view, the switching transistors are arranged within an area where the inductor overlaps the module substrate, whereas at least a portion of the controller IC chip is arranged outside the area.

DC-DC converter with a switching transistor arranged in an area where an inductor overlaps a substrate

The sawtooth wave generation circuit includes: a switch circuit configured to switch a connection state thereof between a first connection state, in which a current from a current source is flowed from a first terminal of the output capacitor to a second terminal of the output capacitor, and a second connection state, in which a current from the current source is flowed from the second terminal of the output capacitor to the first terminal of the output capacitor; a switch control circuit configured such that, in each connection state of the switch circuit, if an output voltage has reached a predetermined threshold which is set in relation to an intermediate voltage, the switch control circuit controls the switch circuit to switch the connection state to the other connection state at least during a part of a predetermined period thereafter.

Sawtooth wave generation circuit

The magnetic field detecting apparatus is provided with: a magnetic field detecting unit for outputting one of two signals having different potential levels from each other in response to a perpheral magnetic field; an energizing control unit for producing a periodic energizing control signal indicative of timing at which the magnetic field detecting unit is energized by employing a clock signal and another signal obtained by frequency-dividing, or frequency-multiplying the clock signal, and for supplying the produced energizing control signal to the magnetic field detecting unit; a first inverting unit for inverting the potential level of the output signal of the magnetic field detecting unit; and an energizing time period control unit for supplying a time period control signal to the energizing control unit, the time period control signal controlling the time period of the energizing control signal in response to the potential level of the output signal of the magnetic field detecting unit, and the potential level of the signal obtained by inverting the potential level of the output signal by the first inverting unit. The energizing time period control unit supplies any one of two pieces of the energizing control signals whose durations and time periods are different from each other, during which the magnetic field detecting unit is not energized, in response to the potential level of the time period control signal supplied from the energizing time period control unit.

Magnetic field detecting apparatus

A voltage detection circuit detects an input voltage in first and second periods to average by using a switch circuit and a sampling circuit. At this time, the input voltage of the second period is added to the input voltage of the first period so that a polarity of variations is opposite, the variations being in relative errors of a plurality of resistors for dividing the input voltage, in input offset voltages of a voltage amplifier for amplifying an inputted minute voltage, and in input offset voltages of a comparator for comparing an amplified voltage value with a certain level.

Voltage detection circuit, overcurrent detection circuit, charging current control system, and voltage detection method

A magnetic field sensor including an amplifier and a magnetic field element for outputting a two-phase signal according to an applied magnetic field strength. Polarities of the two phases of the signal are mutually opposite. The amplifier amplifies the signal and outputs a resulting voltage across a pair of output terminals, which are connected to both ends of a condenser. A switch makes a connection between one of the output terminals and one end of the condenser. The switch closes in a first phase of the two-phase signal and opens in a second phase. A comparator inputting voltage across both ends of the switch converts the result of the comparison, based on a predetermined voltage, into a binary output signal.

Magnetic field sensor having memory element

A magnetic field sensor including an amplifier and a magnetic field element for outputting a signal to a switch circuit according to the strength of an applied magnetic field. The switch circuit outputs a signal selected by an external two-phase signal to an amplifier that amplifies the signal and outputs a resulting voltage to a first end of a memory element. A switch, having one end connected to a second end of the memory element, is controlled by the two-phase signal. The switch closes in a first phase of the two-phase signal causing the memory element to store the output voltage of the amplifier, and opens in a second phase causing a vector sum of the output voltage the amplifier to be stored in the memory element and providing the output voltage to a signal output terminal connected to the second end of the memory element.

Magnetic field sensor

The present invention provides a magnetic sensor with a simple configuration which detects a magnetic field strength of both polarities and which consumes a small amount of power. The magnetic field sensor of the present invention comprises a first switch part which inputs a signal outputted from a magnetoelectric element which outputs a signal corresponding to an applied magnetic field, and which outputs a signal, switching so that a polarity during a first period and a fourth period and a polarity during a second period and a third period are mutually opposite; an amplifier which amplifies an output signal of the first switch part and outputs a signal to its output terminal pair; a memory element, both ends of which are connected to the output terminal pair of the amplifier, and which holds a voltage outputted from the amplifier; a second switch part which is inserted and makes a connection between one of the output terminal and one terminal of the memory element, and which closes during the first period and the third period and opens during the second period and the fourth period; and a switch output terminal which outputs an output signal of a first polarity of the second switch part during the second period, and which outputs an output signal of a second polarity of the second switch part during the fourth period.

Magnetic field sensor, method for detecting magnetic field and device for detecting magnetic field

A magnetic field sensor includes: a Hall element; a voltage amplifier for amplifying an output voltage from the Hall element so as to output an amplified signal; a voltage comparison circuit for receiving the amplified signal; a switch circuit provided between the voltage amplifier and the voltage comparison circuit for inverting a polarity of the amplified signal; and a latch circuit for holding an output signal from the voltage comparison circuit. The voltage comparison circuit inverts a polarity of a hysteresis voltage that determines a reference value of a magnetic field intensity in response to a first synchronizing signal, which triggers a detection of a magnetic field, and a second synchronizing signal following the first synchronizing signal.

Growing community of inventors

Tokyo, Japan

Tadata Hatanaka