Lapis Semiconductor Co., Ltd.

Oki Semiconductor Co., Ltd.

Oki Electric Industry Co., Ltd.

Denso Corporation

Oki Micro Design Co., Ltd.

Kikuo Utsuno

Shigeru Nagatomo

A semiconductor chip having four sides and being substantially formed in a rectangle, and including a first terminal which is located along one side of the four sides of the semiconductor chip and which is to be electrically connected to a solar cell outside the semiconductor chip; a second terminal which is located along the one side of the semiconductor chip and which is to be electrically connected to a secondary cell outside the semiconductor chip; and an interconnection line that electrically interconnects the first terminal and the second terminal.

Semiconductor chip and solar system

A charging control system for charging a secondary battery from a solar battery, including a first path for transmitting power from the solar battery to the secondary battery, a second path for sensing the voltage of the secondary battery, and a comparison unit for comparing the solar battery voltage with the sensed voltage of the secondary battery. The first path includes a first interrupter, controlled by the comparison unit, which interrupts the first path to prevent discharge of the secondary battery through the solar battery when the solar battery voltage falls below the secondary battery voltage. The second path includes a second interrupter that interrupts the second path after the first path is interrupted, to prevent the secondary battery from discharging through the second path when not being charged through the first path.

Charging control system and device

There is provided a semiconductor chip having four sides and being substantially formed in a rectangle, the semiconductor chip including: a first terminal which is located along one side of the four sides of the semiconductor chip and which is to be electrically connected to a solar cell outside the semiconductor chip; a second terminal which is located along the one side of the semiconductor chip and which is to be electrically connected to a secondary cell outside the semiconductor chip; and an interconnection line that electrically interconnects the first terminal and the second terminal.

There is provided a semiconductor device including: a current generation circuit that generates a current; a voltage generation circuit that, using the current generated by the current generation circuit, generates and outputs a predetermined voltage from a reference voltage, with an internal capacitor element that is connected to output of the voltage generation circuit, the internal capacitor element being provided within an integrated circuit on which the device itself is mounted; a storage section that stores a flag indicating a connection state between the output of the voltage generation circuit and an external capacitor element provided externally to the integrated circuit; and a controller that, based on the flag, controls a current amount of the current used by the voltage generation circuit to generate the predetermined voltage.

Semiconductor device and current control method that controls amount of current used for voltage generation based on connection state of external capacitor

A semiconductor device includes a reference voltage generation circuit to which a power source voltage is applied; an output terminal for outputting an output voltage; a determining circuit connected to the reference voltage generation circuit and the output terminal for generating the output voltage according to a determination target voltage; and a constant electric current source connected to the determining circuit and a ground potential for generating a constant electrical current.

Semiconductor device

A voltage change detection device, which reduces a deviation of a detection potential and detects a voltage change within a predetermined detection potential even when the threshold voltage of a field effect transistor is deviated. The voltage change detection device includes a first field effect transistor, a second field effect transistor, and a detection signal generator. The first field effect transistor has a drain connected to a power supply potential, a source connected to a first constant current source or a first resistor at a first node, and a gate connected to a fixed voltage. The second field effect transistor has a drain and a gate connected to the power supply potential and a source connected to a second constant current source or a second resistor at a second node. The detection signal generator generates a detection signal indicating that the power supply potential has crossed a predetermined detection potential.

Voltage change detection device

A charging device can prevent overcharging by coping with a plurality of cell voltages without increasing a circuit area and current consumption. The charging device selects one of at least two judgment voltages in response to a select signal determined depending on a chargeable voltage of a secondary battery. The charging device compares a comparison voltage based on a voltage of a lower stream of a back flow prevention unit with the selected judgment voltage to detect a fully charged state of the secondary battery. The charging device interrupts supply of charging current to the back flow prevention unit upon detecting the fully charged state.

Charging apparatus that can recharge different types of batteries without  overcharging them

A voltage change detection device is provided, which can reduce a deviation of a detection potential and can detect a voltage change within a predetermined detection potential even when the threshold voltage of a field effect transistor is deviated. The voltage change detection device includes a first field effect transistor, a second field effect transistor, and a detection signal generator. The first field effect transistor has a drain connected to a power supply potential, a source connected to a first constant current source or a first resistor at a first node, and a gate connected to a fixed voltage. The second field effect transistor has a drain and a gate connected to the power supply potential and a source connected to a second constant current source or a second resistor at a second node. The detection signal generator generates a detection signal indicating that the power supply potential has crossed a predetermined detection potential according to a comparison between a voltage at the first node and a voltage at the second node.

Growing community of inventors

Miyazaki, Japan

Kikuo Utsuno