A method of wirelessly transmitting power includes: causing a power transmission circuit to transmit, to a master power reception circuit, a portion of power it is capable of transmitting; adjusting operation of a slave power reception unit until a first rectified voltage produced by the master power reception circuit and a second rectified voltage produced by the slave power reception unit are equal; causing the power transmission circuit to transmit additional power to the slave power reception unit, resulting in the first and second rectified voltages being unequal; and adjusting operation of the slave power reception unit until the first and second rectified voltages are again equal. A dummy load is connected to the slave power reception unit prior to causing the power transmission circuit to transmit the additional power, and is disconnected once the first and second rectified voltages are equal.

A method for increasing performance of a voltage-buck switched-mode voltage regulator includes generating a first pulse-width modulation signal based on a clock signal, decreasing a frequency of the clock signal to form a modified clock signal, passing the modified clock signal to a digital modulation circuit as a regulated clock signal; and generating a second pulse-width modulation signal based on the regulated clock signal using the digital modulation circuit. The first pulse-width modulation signal includes a period T1 and an off duration D2 corresponding to a first duty cycle. The off duration D2 is an intrinsic pulse-width modulation signal generation latency. The second pulse-width modulation signal includes a period T2 and the off duration D2. The decreased frequency of the modified clock signal causes T2 to be greater than T1 such that a second duty cycle of the second pulse-width modulation signal is increased relative to the first duty cycle.

A power control integrated circuit (IC) chip can include a direct current (DC)-DC converter that outputs a switching voltage in response to a switching output enable signal. The power control IC chip can also include an inductor detect circuit that detects whether an inductor is conductively coupled to the DC-DC converter and a powered circuit component in response to an inductor detect signal. The power control IC chip can further include control logic that (i) controls the inductor detect signal based on an enable DC-DC signal and (ii) controls the switching output enable signal provided to the DC-DC converter and a linear output disable signal provided to a linear regulator based on a signal from the inductor detect circuit indicating whether the inductor is conductively coupled to the DC-DC converter and the powered circuit component.

An apparatus for charging a battery of a user device includes a charge pump that converts an input voltage, received from a power adapter, to a system voltage that is less than the input voltage based on a ratio of the charge pump, a regulator coupled between the system voltage output by the charge pump and a battery of the user device, the regulator configured to control a battery charging voltage applied to the battery of the user device and to provide isolation between the system voltage that is applied to one or more components of the user device and the battery charging voltage applied to charge the battery of the user device, and a controller configured to determine a difference between the system voltage applied to an input of the regulator and the charging voltage output by the regulator.

A voltage regulator receives a reference voltage and generates a regulated voltage using a MOSFET having a gate terminal configured to receive a control voltage. A charge pump receives the regulated voltage and generates a charge pump voltage in response to an enable signal and a clock signal generated in response to the enable signal. The voltage regulator further includes a first switched capacitor circuit coupled to the gate terminal and configured to selectively charge a first capacitor with a first current and impose a first voltage drop on the control voltage in response to assertion of the enable signal. The voltage regulator also includes a second switched capacitor circuit coupled to the gate terminal and configured to selectively charge a second capacitor with a second current and impose a second voltage drop on the control voltage in response to one logic state of the clock signal.

A current source and/or current sink digital-to-analog converter (DAC) includes a DAC circuit that converts a digital code to an analog current or voltage signal, an optional transconductance circuit that converts a voltage output of the DAC circuit into a current signal, and an output circuit that amplifies a current output of the DAC circuit or optionally amplifies a current output of the transconductance circuit to set a desired high current output for application to an output of the current source and/or current sink DAC. A power supply control current may be coupled to a power supply circuit that supplies power to the output circuit of the current source and/or current sink DAC. The power supply control current adjusts the output of the power supply circuit to cause the current source and/or current sink DAC to operate at a higher power efficiency.

The present disclosure provides a controller for controlling a GaN-based semiconductor device. The controller is configured to receive a current sensing signal V.sub.CS which is indicative of a drain-to-source current of the GaN-based semiconductor device and generate a control driving signal V.sub.DRV to the GaN-based semiconductor device such that a gate-to-source voltage V.sub.GS applied to the GaN-based semiconductor device for switching on the GaN-based semiconductor device is stabilized to a voltage value equal to a reference voltage V.sub.ref over an on-time duration. Impact of the change in the voltage drop across the current sensing resistor to the operation of the GaN-based semiconductor device is eliminated.

A control circuit for a resonant converter, can include: a feedforward circuit configured to generate a feedforward current; a charge feedback circuit configured to receive a resonant current sampling signal representing a resonant current of the resonant converter in a first mode to generate a charge feedback signal, and to receive the resonant current sampling signal and the feedforward current together to generate the charge feedback signal in a second mode; and a driving control circuit configured to generate driving signals according to the charge feedback signal and a first threshold signal, in order to control switching states of power transistors of the resonant converter, where the first threshold signal is generated according to an error compensation signal representing an error information between a feedback signal of an output signal of the resonant converter and a reference signal.

A converter to convert an input voltage into a regulated output current for supplying a load includes a reverse current protection diode having an anode coupled to the input voltage and a cathode, an energy storage element coupled to the cathode of the reverse current protection diode, a high side transistor coupled to the energy storage element and responsive to a high side control signal, and a low side transistor coupled to the energy storage element and responsive to a low side control signal. A controller is configured to generate the high side control signal and the low side control signal such that the low side transistor is enabled and the high side transistor is disabled during a pre-regulation interval.

A system includes a receiver coil configured to be magnetically coupled to a transmitter coil, a rectifier connected to the receiver coil, a first stage and a second stage connected in cascade between the rectifier and a load and a bias voltage source configured to be connected with a first voltage node through a first switch and a second voltage node through a second switch, wherein one of the first voltage node and the second voltage node supplies power to the bias voltage source.