A power control device includes: an output voltage controller configured to control an output voltage based on a feedback voltage corresponding to the output voltage; and an overvoltage protector configured to continue or stop the operation of the output voltage controller based on a first detection result of whether the output voltage has exceeded an output voltage threshold value and a second detection result of whether the feedback voltage has fallen to or below a feedback voltage threshold value.

Power amplifier circuitry includes an amplifier stage, a non-linear compensation network, and non-linear compensation control circuitry. The amplifier stage includes an input and an output, and is configured to receive an input signal at the input and provide an amplified output signal at the output. The non-linear compensation network is coupled between the input and the output of the amplifier stage. The non-linear compensation control circuitry is coupled to the non-linear compensation network and one or more of the input and the output of the amplifier stage. The non-linear compensation control circuitry is configured to adjust a capacitance of the non-linear compensation network to cancel a parasitic capacitance associated with the amplifier stage and thus reduce AM-PM distortion.

A power supply is disclosed. The power supply includes a first switch and a second switch. The gate of the first switch is coupled to the gate of the second switch. The power supply further includes a cutoff switch coupled between the first switch and an input voltage port. A comparator is included for comparing a voltage at a feedback port with a fixed reference voltage. The comparator opens the cutoff switch when the voltage at the feedback port is lower than the fixed reference voltage.

A control circuit of a controller of a photovoltaic system is provided, the control circuit including an input, an output, a start unit consisting of a power dissipation circuit, a voltage regulation circuit and a comparator, a first switch having a position wherein the start unit is connected to the input and an inverse position, and a second switch having a position wherein the input and the output are not connected and an inverse position. The comparator compares the voltages of the dissipation circuit and of the regulation circuit, the comparator outputting a command voltage of the two switches on the basis of the comparison.

An apparatus includes a voltage regulator coupled with a first voltage source, which supplies core memory circuitry. A first transistor is coupled between an output of the voltage regulator and input/output (I/O) circuitry. A second transistor is coupled between a second voltage source and the I/O circuitry, the second voltage source to power a set of I/O buffers. Control logic coupled with gates of the first and second transistors is to perform operations including: causing the second transistor to be activated to permit current to flow from the second voltage source to the I/O circuitry; in response to detecting a current draw from the I/O circuitry that satisfies a first threshold criterion, causing the first transistor to be activated; and causing the second transistor to be deactivated over a time interval during which the I/O circuitry is powered by the first voltage source and the second voltage source.

According to an aspect, a low dropout (LDO) voltage regulator includes a differential amplifier, a pass transistor coupled to an output of the differential amplifier, where the pass transistor is configured to provide an output voltage of the LDO voltage regulator, and a soft-start circuit coupled to the differential amplifier. The soft-start circuit is configured to adjust a soft-start driving signal to control a slope of the output voltage based on the output voltage during a start-up operation of the LDO voltage regulator.

There is to provide a power circuit capable of stabilizing an internal power source voltage and assuring a normal operation of a load circuit. According to one embodiment, the power circuit includes a regulator which generates an output voltage using an entered input voltage, a voltage detecting circuit which detects the output voltage, and a clamp circuit which outputs an internal power source voltage based on the output voltage and in a first failure that the output voltage is larger than a predetermined first voltage, outputs the internal power source voltage suppressed to the first voltage and less, in which the clamp circuit outputs the internal power source voltage to the logic circuit which operates with the internal power source voltage of the first voltage and less and the voltage detecting circuit outputs the first failure to the logic circuit when detecting the first failure.

Compensation circuits, compensated voltage regulators, and methods are provided for stabilizing voltage regulators, or other circuits that use operational amplifiers, over a wide range of output current. The described techniques provide a zero whose frequency varies linearly with an output current, and which can be used to track and compensate for a pole whose frequency similarly varies with the output current. The variable-frequency zero is created using a compensation capacitor placed in series with a variable resistance, wherein the resistance is configured to vary linearly with the output current. A pole-tracking zero generated in this way may be used to overcome difficulties encountered when the gain of a system includes a pole whose frequency varies with output current, and serves to improve the phase margin of amplifier circuitry, including that used within voltage regulators, and/or serves to ensure stability over a wide range of output current.

A power control device includes: an output voltage controller to control the output voltage of a power supply circuit based on a feedback voltage obtained by dividing the output voltage with voltage dividing resistors; and an overvoltage protection circuit to protect against an overvoltage in the output voltage. The overvoltage protection circuit includes: an output voltage detector to detect whether the output voltage has risen above an output voltage threshold value; and a feedback voltage detector to detect whether the feedback voltage has fallen to or below a feedback voltage threshold value. The overvoltage protection circuit continues or stops operation of the output voltage controller based on a first detection output from the output voltage detector and a second detection output from the feedback voltage detector.

In one form, a data transmission system includes transmission and reception circuits. The transmission circuit includes a first driver having an input for receiving a first transmit data signal, an output, a positive power supply terminal for receiving an input/output (I/O) power supply voltage, and a negative terminal for receiving an I/O ground voltage, a second driver having an input for receiving the I/O power supply voltage, an output, and a positive power supply terminal for receiving the I/O power supply voltage, and a third driver having an input for receiving the I/O ground voltage, an output, and a negative power supply terminal coupled to the I/O ground voltage. The reception circuit forms a reference voltage based an average of signal content below a predetermined frequency of outputs of the second and third drivers, and receives a signal from the output of the first driver using the reference voltage.