Abstract: A current controller for generating a control signal which controls supply current flowing from a power source to a load includes an interface circuit which sets a threshold based on an instruction from an outside of the current controller, a threshold setting circuit which stores and outputs the threshold, a sensing circuit which determines a current or a temperature of a sensing element, and outputs a signal indicating that the supply current should be interrupted as the control signal if a determined current or a determined temperature exceeds the threshold, and a sensing control circuit which generates a clock signal including pulses with a predetermined period. The sensing circuit determines the current or the temperature of the sensing element during an active period of the clock signal.

Abstract: A current controller for generating a control signal which controls supply current flowing from a power source to a load includes an interface circuit which sets a threshold based on an instruction from an outside of the current controller, a threshold setting circuit which stores and outputs the threshold, a sensing circuit which determines a current or a temperature of a sensing element, and outputs a signal indicating that the supply current should be interrupted as the control signal if a determined current or a determined temperature exceeds the threshold, and a sensing control circuit which generates a clock signal including pulses with a predetermined period. The sensing circuit determines the current or the temperature of the sensing element during an active period of the clock signal.

Abstract: A current controller for generating a control signal which controls supply current flowing from a power source to a load includes an interface circuit which sets a threshold based on an instruction from an outside of the current controller, a threshold setting circuit which stores and outputs the threshold, a sensing circuit which determines a current or a temperature of a sensing element, and outputs a signal indicating that the supply current should be interrupted as the control signal if a determined current or a determined temperature exceeds the threshold, and a sensing control circuit which generates a clock signal including pulses with a predetermined period. The sensing circuit determines the current or the temperature of the sensing element during an active period of the clock signal.

Abstract: A portable terminal is activated when receiving verification power transmitted in a contactless manner from a charger using electromagnetic coupling between the charger and the portable terminal. The portable terminal sends an electrical signal (wakeup frame) indicating activation immediately after being activated to the charger. Reception of the wakeup frame triggers the power transmitting device to start a verification process on the power receiving device and perform a detection process for a metal foreign object. After authentication is established, the charger transmits normal power to the portable terminal.

Abstract: A contactless power transmitting device is provided with: a primary coil that can be magnetically coupled with a secondary coil of a contactless power receiving device; a first temperature sensor that detects the ambient temperature of the primary coil; a second temperature sensor that detects the temperature at a different location to the first temperature sensor; and a control unit. The control unit is configured to determine whether a value obtained by subtracting the temperature detected by the second temperature sensor from the ambient temperature of the first coil detected by the first temperature sensor exceeds a predetermined threshold value, and to stop the power to the first coil when the subtracted value exceeds the threshold value.

Abstract: A contactless power-receiving device, which is connected to equipment via a connection terminal and which supplies power to the load for the equipment, provided with: a secondary coil which intersects the alternating magnetic flux generated from a primary coil to which an alternating power is supplied; and a control unit which supplies induced electromotive force of the secondary coil to the load. The control unit determines the amount of charge in the load and determines whether or not to supply power to the load on the basis of the determined amount of charge.

Abstract: A primary-side controller (12) retains a reference current value corresponding to an input current measured in the previous detection cycle by an input current measurement unit (11), in a charging state. The primary-side controller (12) adds the retained reference current value and a predetermined current value, and generates a first threshold value. When the input current measured by the input current measurement unit (11) in the latest detection cycle is equal to or greater than the first threshold value, a determination is made that a foreign metal is present in the vicinity of a first coil (L1).

Abstract: The invention provides a switching power supply device that can restrain the variation in the ripple of the output voltage corresponding to the variation in the input voltage and a control device thereof. When output voltage Vout is higher than a target value, switching converter circuit 10 is set to a second state (a state of discharging the power stored in inductor L1 to terminal To). When output voltage Vout is lower than the target value, switching converter circuit 10 is set to a first state (a state of storing the power input from terminal Ti in inductor L1) for a prescribed period of time and is then returned to the second state. Also, when the current flowing through inductor L1 exceeds a threshold value, switching converter circuit 10 is set to the second state.

Abstract: The circuit device for detection includes: a first terminal 3 and a second terminal 4; a reference terminal 5; a reception frequency tuning section including a first tuning capacitor 6a provided between the first terminal 3 and the reference terminal 5, a second tuning capacitor 6b provided between the second terminal 4 and the reference terminal 5, a first switch 9a connected in series with the first tuning capacitor 6a between the first terminal 3 and the reference terminal 5, and a second switch 9b connected in series with the second tuning capacitor 6b between the second terminal 4 and the reference terminal 5; and a control circuit section including a first control circuit 12a for controlling the operation of the first switch 9a and a second control circuit 12b for controlling the operation of the second switch 9b.

Abstract: This invention prevents undershoot, etc., occurring in the output during the transition from intermittent control mode to continuous control mode to hinder stability, responsiveness, and low power consumption.

Abstract: A synchronous rectifying type switching regulator control circuit has a first reference voltage circuit that receives a soft start signal from a soft start circuit and outputs a first reference voltage. An error amplifying circuit amplifies a difference of the first reference voltage and a divided voltage from a voltage dividing circuit and outputs an error voltage Verr. A first comparing circuit compares a triangular wave from an oscillator with the error voltage Verr and outputs an output pulse Vcomp. A second comparing circuit compares a second reference voltage from a second reference voltage circuit with the error voltage Verr and outputs a voltage ERRcomp. A logic circuit receives the soft start signal, the output pulse Vcomp, and the voltage ERRcomp and outputs a voltage Vcomp2. The logic circuit outputs the output pulse Vcomp when the error voltage Verr is higher than the second reference voltage during a soft start period.

Abstract: This invention prevents undershoot, etc., occurring in the output during the transition from intermittent control mode to continuous control mode to hinder stability, responsiveness, and low power consumption.

Abstract: The invention provides a switching power supply device that can restrain the variation in the ripple of the output voltage corresponding to the variation in the input voltage and a control device thereof. When output voltage Vout is higher than a target value, switching converter circuit 10 is set to a second state (a state of discharging the power stored in inductor L1 to terminal To). When output voltage Vout is lower than the target value, switching converter circuit 10 is set to a first state (a state of storing the power input from terminal Ti in inductor L1) for a prescribed period of time and is then returned to the second state. Also, when the current flowing through inductor L1 exceeds a threshold value, switching converter circuit 10 is set to the second state.

Abstract: An overcurrent protection circuit for a voltage regulator has a first transistor having a gate for connection to a gate of an output transistor of the voltage regulator, a resistor connected to a drain of the first transistor, an output voltage detecting transistor having a gate connected to an output terminal of a dividing resistance circuit of the voltage regulator, and a current mirror circuit having an input terminal connected to the drain of the output voltage detecting transistor. A second transistor has a gate connected to the drain of the first transistor and a drain connected to an output terminal of the current mirror circuit. A third transistor has a gate connected to the output terminal of the current mirror circuit and a drain for connection to the gate of the output transistor of the voltage regulator.

Abstract: The present invention provides a voltage regulator which has high-speed responsibility with a low consumption current, and which can stably operate with a low output capacity. The voltage regulator includes: a reference voltage circuit, a voltage division circuit, a differential amplifier, an output transistor, a MOS transistor which has a gate to which an output of the differential amplifier is connected, a constant current circuit connected between a drain of the MOS transistor and the ground, and parallel-connected resistor and capacitor for phase compensation are connected between the drain of the MOS transistor and a gate of the output transistor.

Abstract: To obtain an overcurrent protection circuit capable of controlling a short circuit current generated upon overcurrent protecting operation by adding a simple circuit to a drooping type overcurrent protection circuit. The voltage regulator is structured to vary a value of a short circuit current generated upon overcurrent protecting operation by controlling a gate voltage of an output transistor in accordance with a value of an output voltage.

Abstract: The present invention provides a voltage regulator which has high-speed responsibility with a low consumption current, and which can stably operate with a low output capacity. The voltage regulator includes: a reference voltage circuit, a voltage division circuit, a differential amplifier, an output transistor, a MOS transistor which has a gate to which an output of the differential amplifier is connected, a constant current circuit connected between a drain of the MOS transistor and the ground, and parallel-connected resistor and capacitor for phase compensation are connected between the drain of the MOS transistor and a gate of the output transistor.

Abstract: Provided is a synchronous rectifying type switching regulator control circuit capable of performing stable power supply even when a difference between input and output voltages is small during soft start at the time of turning on a power source. During the soft start at the time of turning on the power source, switching operation is performed after energy is surely held in a coil by providing a pulse outputted to a synchronous rectifying circuit with duty limit.

Abstract: The present invention provides a PWM switching regulator circuit capable of reducing power consumption while it is operated under a light load. When load condition is changed from a heavy load to a light load, an internal oscillation frequency is changed from a first oscillation frequency to a second oscillation frequency lower than the first oscillation frequency, while when the load condition is changed from the light load to the heavy load, the internal oscillation frequency is returned from the second oscillation frequency back to the first oscillation frequency in accordance with an ON/OFF ratio of a signal used to control a switch of a PWM switching regulator circuit.

Abstract: To provide a resistor circuit with which a resistance ratio among voltage division resistors in a semiconductor integrated circuit can be realized with high accuracy. The resistor circuit of the present invention includes: a reference resistor portion; and a resistor portion including resistor elements and fuse connected in parallel with the resistor elements, respectively, for trimming the resistor elements. The resistor elements are arranged in order from the resistor element having a largest resistance value so as to be adjacent to the reference resistor portion in the periphery of the reference resistor portion. As a result, it is possible to obtain accurately the ratio between a resistance value of a reference resistor and a desired resistance value determined with the ratio from the resistance value of the reference resistor.