Kabushiki Kaisha Tokai Rika Denki Seisakusho

Junichi Matsubara

Satoki Uruno

Kengo Shima

Yuichiro Mori

Natsuki Arakawa

Daisuke Aoki

Koji Saito

Yusuke Kamiya

A constant voltage device include a diode; a switch including one terminal connected to a ground potential and another terminal connected both to an anode terminal of the diode and to a drain of a PMOS transistor having a source applied with a power source voltage; a voltage generation circuit configured to generate a voltage of a predetermined magnitude; and a differential amplifier that includes a non-inverting input terminal to which both a cathode terminal of the diode and an output terminal of the voltage generation circuit are connected, and that is configured to change a supply route of a reference voltage applied to the non-inverting input terminal according to a state of the switch. The voltage generation circuit is configured to employ an output voltage based on the reference voltage and amplified by the differential amplifier to generate the reference voltage.

Constant voltage device

A semiconductor integrated circuit includes a constant-voltage circuit that outputs a constant voltage and a constant-current circuit. The constant-current circuit includes a first transistor. A voltage input as an input voltage to a first gate electrode of the first transistor is equal to the node voltage at an intermediate node in a connection path between the output of the constant-voltage circuit and an external resistor. A source region of the first transistor is connected to a fixed power supply, and a drain region of the first transistor is connected to the external power supply via a load. In the first transistor, a constant current can be made to flow between the source region and the drain region based on the input voltage. A constant-current drive system in which the semiconductor integrated circuit and the external resistor have been mounted on a circuit board is also constructed.

Circuit and constant-current drive system having adjustable constant current output

A level shift device includes a high breakdown voltage element in which a voltage of an internal power supply part is applied to a gate, an external input signal is input from outside to one of a source and a drain, and the other one of the source and the drain outputs an intermediate output signal of the same phase as that of the external input signal, and a comparator comparing the intermediate output signal with a threshold value so as to perform conversion into a Hi/Lo signal defined by a voltage of the internal power supply part and outputting the signal to an internal processing circuit. The high breakdown voltage element, the comparator, the processing circuit, and the internal power supply part are enclosed in the device.

Level shift device and IC device

A signal processing device includes an input terminal configured to be input with an input signal that is active high or an input signal that is active low, a switching terminal connectable to a power supply or ground, a selection circuit configured to select and output the input signal that is active high in a case that the switching terminal is connected to the power supply and select and output the input signal that is active low in a case that the switching terminal is connected to the ground.

Signal processing device

The present disclosure provides a level shifter including: a level shifter section that is driven by a first power source voltage, and that, in accordance with switching of an input signal of a voltage lower than the first power source voltage, switches an output signal that has been level-shifted, from the first power source voltage to a voltage lower than the first power source voltage; and a threshold voltage changing circuit that, in accordance with a switching direction of the input signal, changes a threshold voltage of the input signal for switching the output signal.

Level shifter

A level shifter that includes: a power supply system current source; a second transistor having a third main electrode that is connected to an input voltage signal terminal, a fourth main electrode that is connected to an output voltage signal terminal, and a second control electrode that is connected to a third power supply voltage having a voltage that is lower than a first power supply voltage and higher than a second power supply voltage; a second resistor; and a third transistor having a fifth main electrode that is connected to the second end of the second resistor, a sixth main electrode that is connected to the second power supply voltage, and a third control electrode that is connected to a first control electrode of a first transistor of the power supply system current source.

An indicator drive circuit includes a current mirror circuit including a first transistor located at a control side and a second transistor located at a controlled side, a current through the current mirror circuit being switched by an external control signal, a current source adapted to feed a control current to the first transistor of the current mirror circuit, and a switching element adapted to be driven by a current through the second transistor of the current mirror circuit and to switch on or off an indicator light source. The current source includes two transistors cascode-connected.

Growing community of inventors

Aichi, Japan

Junichi Matsubara