An apparatus, system, and method are disclosed for compensating input offset of an amplifier having first and second amplifier output nodes. The method comprises generating a proportional-to-absolute temperature (PTAT) current, generating a complementary-to-absolute temperature (CTAT) current, and selecting, based on the input offset, one of the first and second amplifier output nodes into which a compensation current is to be coupled. The compensation current is based on a selected one of the PTAT current and CTAT current.

A method and system for linearizing a Radio Frequency Power Amplifier (RFPA) is disclosed. The method comprises calibrating signals in the RFPA to linearize the RFPA, using at least one of a first signal, a second signal, a third signal, and a fourth signal. The first signal is generated corresponding to ambient temperature. The second signal is generated corresponding to process corner of transistors in the RFPA. The third signal is generated corresponding to power supply voltage. The fourth signal is generated by feeding back output of the RFPA.

The present invention provides an RF power amplifier architecture which with dynamic digital control of the amplification by incorporating digitized RF input and output signal envelope data and environmental temperature sensor(s) readings into an arbitrary control algorithm implemented on a digital processor. Via the combination of digitally controlled DC/DC converter and a D/A converter, the quiescent bias of the power FET of the RF output stage can become a realization of virtually any function of the feedback and input data.

In a radio frequency (RF) amplifier system and a heat dissipation device thereof, the RF amplifier system includes an RF amplifier and a heat dissipation device. The RF amplifier includes an RF power element. The heat dissipation device includes a heat conduction board, a plurality of heat pipes and fins. The heat conduction board is thermally conductively coupled to the RF power element, and one end of the heat pipe is thermally conductively coupled to the heat conduction board. The fins are arranged in parallel and spaced from each other. The other end of each of the heat pipes is inserted through the fins. The heat of the RF power element is conducted to the heat conduction board and the heat pipe, and then the heat is quickly conducted to the fins to be dissipated away quickly, and the RF power element can quickly reach a stable temperature.

An amplifier module having a surface-mounting carrier with a base and lid is disclosed. The base in a top surface thereof provides a die pad on which a transistor is mounted, and a back surface thereof provides a back pad electrically and thermally connected to the die pad. The back pad has an area wider than the area of the die pad. The heat conduction from the transistor to the host board on which the amplifier module is mounted is effectively enhanced.

Provided are a gain compensation device and a bias circuit device. A compensation bias current is generated by the gain compensation device to compensate the gain deviation of power amplifier and improve stability of power amplifier. Through high-temperature compensation unit and low-temperature compensation unit in different gears, gain of power amplifier is compensated along with temperature changes, thereby improving feasibility of the gain compensation device. It takes small space, and the circuit only includes the circuits corresponding to high-temperature compensation unit and low-temperature compensation unit, so the circuit is relatively simple and beneficial to miniaturization. In the bias circuit device, based on an initial bias current provided by a bandgap reference, the gain compensation device is added to generate a compensation bias current, and the initial bias current and compensation bias current are superimposed, so that the gain of power amplifier is further compensated, which improves stability of power amplifier.

A temperature detector is used to detect a temperature of a circuit under test, and includes a temperature coefficient component, a multiplier, an impedance component and a node. The temperature coefficient component is arranged in proximity to the circuit under test. A control terminal of the multiplier is coupled to a second terminal of the temperature coefficient component. The impedance component is coupled between the second terminal of the temperature coefficient component and the control terminal of the multiplier, or between a second terminal of the multiplier and a third voltage terminal. The node is formed between the second terminal of the temperature coefficient component and the control terminal of the multiplier. A voltage at the node and an amplified detection current flowing to a first terminal of the multiplier are positively correlated to the temperature of the circuit under test.

A bias circuit includes a current generating circuit generating an internal base current based on a reference current, a bias output circuit generating a base bias current based on the internal base current and outputting the base bias current to an amplifying circuit, and a temperature compensation circuit regulating the base bias current based on a temperature voltage reflecting a change in ambient temperature.

An audio amplifier and a warning sound amplifier are connected in parallel to each other, relative to a voice coil of a loudspeaker. A resistor having an impedance greater than an impedance of the voice coil is connected to the voice coil and is also connected to the warning sound amplifier. An audio signal from the warning sound amplifier is input to the voice coil via the resistor. Thus, since the warning sound amplifier is connected to the resistor having the impedance greater than the impedance of the voice coil of the loudspeaker, even in a case where only the audio amplifier is operated, a large current is prevented from flowing into the warning sound amplifier.

An audio amplifier and a warning sound amplifier are connected in parallel to each other, relative to a voice coil of a loudspeaker. A resistor having an impedance greater than an impedance of the voice coil is connected to the voice coil and is also connected to the warning sound amplifier. An audio signal from the warning sound amplifier is input to the voice coil via the resistor. Thus, since the warning sound amplifier is connected to the resistor having the impedance greater than the impedance of the voice coil of the loudspeaker, even in a case where only the audio amplifier is operated, a large current is prevented from flowing into the warning sound amplifier.