An electrical system may include a mounting surface, a component configured for connection with the mounting surface and configured to move relative to the mounting surface, and/or an orientation sensor configured to determining an orientation of the component relative to the mounting surface. The orientation sensor may include a first sensor (e.g., a magnetometer, an accelerometer, a gyroscope, etc.) connected, at least indirectly, to the mounting surface, and a second sensor (e.g., a magnetometer, an accelerometer, a gyroscope, etc.) connected to move with the component. The orientation sensor may include an electronic controller. The electronic controller may be configured to compare first information from the first sensor to second information from the second sensor to determine the orientation of the component relative to the mounting surface.

An integrated circuit is built with enhancement mode Gallium Nitride (GaN) components. The integrated circuit comprises a comparator circuit which compares an input voltage with a reference voltage to provide a controllable constant current source, the comparator having a drive transistor having a positive threshold voltage, the drive transistor being switched on and off based on a comparison result of the comparator. The circuit may drive ring oscillators and may provide pulse width modulation with variable duty cycle at constant frequency.

An alternator and a rectifier thereof are provided. The rectifier includes a transistor and a gate voltage control circuit. The transistor is controlled by a gate voltage. The gate voltage control circuit generates the gate voltage according to a voltage difference between an input voltage and a rectified voltage. During a first time interval after the voltage difference drops to a first preset threshold voltage, the gate voltage control circuit determines whether the voltage difference is less than a second preset threshold voltage, and decides whether to provide the gate voltage to turn on the transistor. When the transistor is turned on, the voltage difference substantially equals to a first reference voltage. And during a second time interval, the gate voltage control circuit regulates the gate voltage to set the voltage difference substantially to a second reference voltage.

A fast-switching power management circuit is provided. The fast-switching power management circuit is configured to generate an output voltage(s) based on an output voltage target that may change on a per-frame or per-symbol basis. In embodiments disclosed herein, the fast-switching power management circuit can be configured to adapt (increase or decrease) the output voltage(s) within a very short switching interval (e.g., less than one microsecond). As a result, when the fast-switching power management circuit is employed in a wireless communication apparatus to supply the output voltage(s) to a power amplifier circuit(s), the fast-switching power management circuit can quickly adapt the output voltage(s) to help improve operating efficiency and linearity of the power amplifier circuit(s).

In a general aspect, a circuit can include a pass device configured to receive an input voltage and provide an output voltage. The circuit can further include a current sink coupled with a control terminal of the pass device, the current sink being configured to discharge the control terminal of the pass device to limit the output voltage in response to the input voltage exceeding a threshold voltage. The circuit can also include a switch coupled in series with the current sink, the switch being configured to enable the current sink in response to the input voltage exceeding the threshold voltage.

A method for operating a normally off or normally on power semiconductor element. A threshold voltage change in a threshold voltage of the power semiconductor element in relation to a reference threshold voltage is determined. A switch-on gate voltage is applied between a gate terminal and a source terminal of the power semiconductor element for the purpose of switching on the power semiconductor element is changed by the threshold voltage change in relation to a reference switch-on gate voltage corresponding to the reference threshold voltage.

Disclosed herein is a bridge rectifier and associated control circuitry collectively forming a “regtifier”, capable of both rectifying an input time varying voltage as well as regulating the rectified output voltage produced. To accomplish this, the gate voltages of transistors of the bridge rectifier that are on during a given phase may be modulated via analog control (to increase the on-resistance of those transistors) or via pulse width modulation (to turn off those transistors prior to the end of the phase). Alternatively or additionally, the transistors of the bridge rectifier that would otherwise be off during a given phase may be turned on to help dissipate excess power and thereby regulate the output voltage. A traditional voltage regulator, such as a low-dropout amplifier, is not used in this design.

A driver circuit for controlling a P-channel MOSFET includes a first voltage divider connected to a source terminal of the P-channel MOSFET, a first sub-transistor including a first collector terminal, a first emitter terminal and a first base terminal, the first collector terminal is connected to the first voltage divider, a second sub-transistor including a second collector terminal, a second emitter terminal and a second base terminal, the second emitter terminal is connected to a gate terminal of the P-channel MOSFET, and the second base terminal is connected to a first connection node, a third sub-transistor including a third collector terminal, a third emitter terminal and a third base terminal, the third emitter terminal is connected to the second emitter terminal, and the third collector terminal is connected to a ground, and a first resistor connected between the second collector terminal and the second emitter terminal.

The disclosure relates to power semiconductor devices in GaN technology. The disclosure proposes an integrated auxiliary gate terminal (15) and a pulldown network to achieve a normally-off (E-Mode) GaN transistor with threshold voltage higher than 2V, low gate leakage current and enhanced switching performance. The high threshold voltage GaN transistor has a high-voltage active GaN device (205) and a low-voltage auxiliary GaN device (210) wherein the high-voltage GaN device has the gate connected to the source of the integrated auxiliary low-voltage GaN transistor and the drain being the external high-voltage drain terminal and the source being the external source terminal, while the low-voltage auxiliary GaN transistor has the gate (first auxiliary electrode) connected to the drain (second auxiliary electrode) functioning as an external gate terminal. In other embodiments a pull-down network for the switching-off of the high threshold voltage GaN transistor is formed by a diode, a resistor, or a parallel connection of both connected in parallel with the low-voltage auxiliary GaN transistor.

According to one aspect of embodiments, a drive circuit of a normally-ON transistor includes: a normally-OFF transistor that includes a main current path connected in serial to a main current path of the normally-ON transistor; and a buffer circuit that supplies, to a gate of the normally-ON transistor, a control signal for controlling turning ON and OFF of the normally-ON transistor, whose high-voltage side and low-voltage side are biased by a bias voltage supplied from a power source unit.