A power amplifier includes an over-current protection loop and/or an over-voltage protection loop to assist in preventing operation outside a safe operation zone. In a further exemplary aspect, triggering of the over-current protection loop adjusts a threshold voltage for the over-voltage protection loop. In further exemplary aspects, the over-current protection loop may adjust not only a bias regulator, but also provide an auxiliary control signal that further limits signals reaching the power amplifier. In still further exemplary aspects, the over-voltage protection loop may operate independently of the over-current protection current loop or the over-voltage protection loop contribute to an over-current protection signal.

An overcurrent protection circuit includes: a first transistor and a second transistor configured to form an amplifier input stage that receives input of a detection signal according to a monitoring target current; and a third transistor configured to form an amplifier output stage that generates a current output signal according to a difference between the detection signal and a reference signal and causes the current output signal to be negatively fed back to the amplifier input stage, wherein the monitoring target current is limited based on the current output signal output from the third transistor.

An auxiliary control circuit (100) for a power amplification module, a power amplification module, and a communication device. The auxiliary control circuit (100) for the power amplification module comprises a main control chip (201), a current detection chip (12), and a precision adjustment unit (14). The precision adjustment unit (14) is connected in parallel to a precision control resistor of the current detection chip (12), and a switch control terminal of the precision adjustment unit (14) is electrically connected to the main control chip (201) and is used for adjusting an output voltage amplification factor of the current detection chip (12) when a switch signal outputted by the main control chip (201) is received. A detection input terminal of the current detection chip (12) is used for accessing a voltage to be measured of a power amplifier transistor power supply circuit (102) of the power amplification module. A detection output terminal of the current detection chip (12) is electrically connected to the main control chip (201). The main control chip (201) is used, upon receipt of a voltage signal outputted by the current detection chip (12), to measure and calculate so as to obtain a power amplification current corresponding to the voltage to be measured. By providing the precision adjustment unit (14) on the power amplification module for cooperation with the main control chip (201) and the current detection chip (12), the effect of greatly improving the detection precision of a power amplification current is achieved.

An amplifier overload power limit circuit, system, and a method thereof comprising a monitoring of a current gain of a BJT based on a current detector and limiting power to the BJT based on the monitored current gain to prevent the BJT from driven into a saturation mode and the amplifier overdrive.

An audio signal reproduction apparatus includes a temperature detection unit detecting a temperature of a battery pack, a voltage detection unit detecting a voltage of the battery pack, and a control unit performing an output control on a basis of temperature information detected by the temperature detection unit and voltage information detected by the voltage detection unit.

The present disclosure relates to devices and methods for detecting and preventing occurrence of a saturation state in a power amplifier. A power amplifier module can include a power amplifier including a cascode transistor pair. The cascode transistor pair can include a first transistor and a second transistor. The power amplifier module can include a current comparator configured to compare a first base current of the first transistor and a second base current of the second transistor to obtain a comparison value. The power amplifier module can include a saturation controller configured to supply a reference signal to an impedance matching network based on the comparison value. The impedance matching network can be configured to modify a load impedance of a load line in electrical communication with the power amplifier based at least in part on the reference signal.

A system for sensing an electrical quantity may include a sensing stage configured to sense the electrical quantity and generate a sense signal indicative of the electrical quantity, wherein the electrical quantity is indicative of an electrical signal generated by a Class-DG amplifier configured to drive a load wherein the Class-DG amplifier has multiple signal-level common modes and a common-mode compensator configured to compensate for changes to a common-mode voltage of a differential supply voltage of the driver occurring when switching between signal-level common modes of the Class-DG amplifier.

A system comprises a positive voltage supply node and a negative voltage supply node configured for connection to a load, a power source coupled between the positive voltage supply node and the negative voltage supply node, an energy storage device, a solid-state switch, and a control system. The energy storage device and the solid-state switch are connected in series between the positive voltage supply node and the negative voltage supply node. The control system is configured to control activation and deactivation of the solid-state switch to (i) allow the energy storage device to be discharged and supply power to a load, and to (ii) modulate an amount of charging current that flows through the energy storage device from the power source (or load) to recharge the energy storage device.

A method for calibrating a fully-differential input system may include determining a first voltage of a first node of the fully-differential input system, wherein the first node is coupled at the first node to a plurality of first resistors in a first star configuration, determining a second voltage of a second node of the fully-differential input system, wherein the second node is coupled at the second node to a plurality of second resistors in a second star configuration, each resistor of the plurality of second resistors corresponding to a respective resistor of the plurality of first resistors, and trimming individual resistances of the plurality of first resistors and the plurality of second resistors in order to maintain a difference of a first voltage at the first node and a second voltage of the second node at approximately zero.

An electronic device and method thereof of are provided to prevent burnout due to overcurrent. An electronic device includes a power amplifier configured to amplify a transmission signal; a battery configured to provide a bias voltage to the at least one power amplifier; and an overcurrent protection circuit configured to prevent overcurrent from flowing through the power amplifier. The overcurrent protection circuit includes a configurer configured to configure a reference current value, based on the power amplifier; a measurer configured to measure a bias current value due to the bias voltage; a comparator configured to compare the measured bias current value with the reference current value; and a controller configured to recognize overcurrent flowing through the power amplifier and control provision of the bias voltage, based on a result of the comparison.