摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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. In addition, the threshold value of the inductor current is adjusted corresponding to the ratio between input voltage Vin and output voltage Vout, so that the variation in the ripple of output voltage Vout occurring together with the variation in that ratio can be restrained.
摘要:
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.
摘要:
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.
摘要:
Reducing the chip area while improving the manufacturing efficiency as well as reducing costs in a semiconductor integrated circuit device such as a thermal head driver IC. A plurality of terminal electrodes were provided within an external data input/output circuit with an input terminal and output terminal being electrically connected to each other. In addition, an input/output protection circuit was provided to a respective one of such plurality of terminal electrodes with the input terminal and output terminal electrically connected together.
摘要:
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).