Abstract: To provide a voltage regulator capable of using as a capacitor of a phase compensation circuit, a capacitor large in capacitance value per unit area and thin in oxidation film thickness. A voltage limitation circuit that limits so that a voltage applied across a capacitor of a phase compensation circuit does not reach a predetermined value or greater is provided in parallel with the capacitor.

Abstract: Provided is an ESD protection circuit for CDM capable of preventing a high current from flowing and preventing breakage when a battery is connected with reverse polarity. The ESD protection circuit employs a circuit configuration in which transistor elements are interposed in series to OFF transistors (11 and 13) included in the ESD protection circuit for CDM so that parasitic diodes of the transistor elements are connected to parasitic diodes of the OFF transistors in a reverse direction.

Abstract: Provided is a voltage regulator capable of preventing a large current from flowing even when a battery (110) is connected with reverse polarity by mistake. The voltage regulator employs a circuit configuration in which a substrate potential (n-well) of an output transistor (103) of the voltage regulator is not fixed to a potential of a VDD terminal, and a power supply of a reference voltage circuit (101) and an error amplifier (102) is not fixed to the VDD terminal.

Abstract: A power generation circuit has one of an antenna or a coil that receives an ambient radio wave. A rectifying circuit is connected to the antenna or the coil for rectifying a signal from the antenna or the coil receiving the ambient radio wave. A booster circuit is connected to and boosts an output of the rectifying circuit. A storage circuit is connected to the booster circuit and stores an output power obtained from the rectifying circuit for driving a load without the use of a power source or a battery. A switching circuit is operable in an ON-state thereof to connect the storage circuit to the load when a voltage of the storage circuit is equal to or greater than a preselected voltage.

Abstract: Provided is an ESD protection circuit for CDM capable of preventing a high current from flowing and preventing breakage when a battery is connected with reverse polarity. The ESD protection circuit employs a circuit configuration in which transistor elements are interposed in series to OFF transistors (11 and 13) included in the ESD protection circuit for CDM so that parasitic diodes of the transistor elements are connected to parasitic diodes of the OFF transistors in a reverse direction.

Abstract: Provided is a voltage regulator capable of preventing a large current from flowing even when a battery (110) is connected with reverse polarity by mistake. The voltage regulator employs a circuit configuration in which a substrate potential (n-well) of an output transistor (103) of the voltage regulator is not fixed to a potential of a VDD terminal, and a power supply of a reference voltage circuit (101) and an error amplifier (102) is not fixed to the VDD terminal.

Abstract: A power generation circuit using an electromagnetic wave which does not require any additional energy is provided. Power generation is performed by utilizing the electromagnetic wave existing in a space for living.

Abstract: A power generation circuit generates and stores electric power utilizing electromagnetic wave energy. The power generation circuit has one of an antenna or a coil that receives an electromagnetic wave. A rectifying circuit is formed on a silicon substrate and rectifies a signal from the antenna or the coil. A storage circuit stores an output power obtained from the rectifying circuit for driving a load. A MOS transistor has a source and a drain connected to an output of the storage circuit and the load, respectively, so that the load is connected to the storage circuit in accordance with a threshold voltage of the MOS transistor.

Abstract: An electronic circuit device comprises a silicon substrate having front and rear surfaces, a semiconductor element formed on the front surface, and at least one through-hole penetrating through the front surface and the rear surface. At least one passive element is supported by the silicon substrate. At least one connecting element is disposed in the through-hole of the silicon substrate for electrically connecting the semiconductor element to the passive element.

Abstract: Provided is a humidity sensor whose electrode is set to have an island-like configuration and is enclosed by a humidity sensitive film. As a result, in the humidity sensor, adhesion property between the humidity sensitive films on the electrode is enhanced and thus high reliability is achieved.

Abstract: An electronic circuit device comprises a silicon substrate having front and rear surfaces, a semiconductor element formed on the front surface, and at least one through-hole penetrating through the front surface and the rear surface. At least one passive element is supported by the silicon substrate. At least one connecting element is disposed in the through-hole of the silicon substrate for electrically connecting the semiconductor element to the passive element.

Abstract: Provided is a switching regulator having satisfactory energy conversion efficiency during light load conditions. Such a structure is employed that an oscillating frequency for the switching regulator and a drive capability of a switch element are variable and such a control is taken that during the light load, the oscillating frequency for the switching regulator or the drive capability of the switch element is reduced.

Abstract: A system for measuring the transmission characteristic of an xDSL system that implements high-speed data communication over existing copper telephone wires connecting an office and a subscriber includes a polling device included in the outside line of an xDSL circuit, which is installed in an office, for polling a subscriber line. A noise level measuring circuit measures the existing level of cross-talk noise on the subscriber line. A decision circuit determines, based on the existing level of cross-talk noise measured, whether or not the subscriber line is usable.

Abstract: Provided is a humidity sensor whose electrode is set to have an island-like configuration and is enclosed by a humidity sensitive film. As a result, in the humidity sensor, adhesion property between the humidity sensitive films on the electrode is enhanced and thus high reliability is achieved.

Abstract: A capacitance type dynamic quantity sensor has a first substrate, a second substrate disposed over the first substrate, and first and second electrodes each disposed on a main surface of a respective one of the first and second substrates. Each of the first and second electrodes has through-holes formed in a portion thereof. A third substrate is disposed between and connected to the main surface of each of the first and second substrates. A vibration member is mounted on the third substrate so as to confront the first and second electrodes with gaps therebetween. The vibration member is mounted on the third substrate to undergo vibrational movement in response to application of an acceleration or an angular velocity to the vibration member so that the capacitance type dynamic quantity sensor detects a dynamic quantity in accordance with a change in capacitance between the first and second electrodes due to vibrational movement of the vibration member.

Abstract: A battery pack has a secondary battery connected to a plus side terminal. A protective circuit protects the secondary battery from overcharge and over-discharge. A calculation circuit operates with a minus side terminal as a reference for calculating a remaining capacity of the secondary battery. An N-channel MOS transistor is connected between the secondary battery and the minus terminal for controlling charge and discharge of the secondary battery in accordance with a signal from the protective circuit. A level shifter circuit is connected between the calculation circuit and a communication terminal.

Abstract: Provided is a switching regulator having satisfactory energy conversion efficiency during light load conditions. Such a structure is employed that an oscillating frequency for the switching regulator and a drive capability of a switch element are variable and such a control is taken that during the light load, the oscillating frequency for the switching regulator or the drive capability of the switch element is reduced.

Abstract: An LED drive circuit having reduced power consumption has a constant current generating circuit for driving a plurality of LEDs and at least one switch connected to a respective LED for periodically turning on and off the respective LED at a rate higher than a visual perception rate to reduce power consumption.

Abstract: A power generation circuit using an electromagnetic wave which does not require any additional energy is provided. Power generation is performed by utilizing the electromagnetic wave existing in a space for living.

Abstract: An electronic circuit device having a silicon substrate is provided comprising: a silicon substrate having a semiconductor element and a recess; and at least one passive element which is formed by a process different from a silicon planar process by which the semiconductor element is formed. In the electronic circuit device, the passive element is entrenched in the recess of the silicon substrate, and the semiconductor element formed on the silicon substrate is electrically connected to the passive element.