An enhanced current mirror can be utilized to accurately control a bias current associated with an amplifier. A current controller component (CCC) can employ the enhanced current mirror and can be associated with the amplifier. The CCC can comprise a comparator that can compare an adjusted supply voltage level to a reference voltage level, the adjusted supply voltage level relating to a supply voltage level of a supply voltage supplied to the amplifier and CCC. The CCC can control switching of an operational state of a transistor of the comparator to switch in or out a resistance of a reference resistor component associated with the supply voltage, based on a result of the comparison of the adjusted supply voltage level to the reference voltage level, to facilitate accurately controlling an amount of bias current associated with the amplifier. The CCC and amplifier can be situated on the same die.

An amplifier circuit amplifies a radio-frequency signal. The amplifier circuit includes an amplifier, an input matching circuit connected to an input side of the amplifier and matches impedance, and a protection circuit connected to a node in a path within a path between an input matching circuit and the amplifier. The protection circuit includes a first diode connected between the node and a ground, and a second diode connected in parallel with the first diode and connected in a direction opposite to the first diode between the node and the ground. A threshold voltage of each of the first diode and the second diode is greater than a maximum voltage amplitude of the input signal at the node and is less than a difference between a withstand voltage of the amplifier and the bias voltage.

Methods and circuital arrangements for turning OFF branches of a multi-branch cascode amplifier are presented. First and second switching arrangements coupled to a branch allow turning OFF the branch while protecting transistors of the branch from a supply voltage that may be greater than a tolerable voltage of the transistors. The first switching arrangement includes a transistor-based switch that is in series connection with the transistors of the branch. The first switching arrangement drops the supply voltage during the OFF state of the branch and provides a conduction path for a current through the branch during the ON state of the branch. A resistor and a shunting switch are coupled to a gate of the transistor-based switch to reduce parasitic coupling effects of the transistor-based switch upon an RF signal coupled to the branch during the ON state and OFF state of the branch.

Microwave amplifiers tolerant to electrical overstress are provided. In certain embodiments, a monolithic microwave integrated circuit (MMIC) includes a signal pad that receives a radio frequency (RF) signal, a ground pad, a balun including a primary section that receives the RF signal and a secondary section that outputs a differential RF signal, an amplifier that amplifies the differential RF signal, and a plurality of decoupling elements, some of them electrically connected between the primary section and the ground pad, others electrically connected in the secondary section to a plurality of the amplifier's nodes, and operable to protect the amplifier from electrical overstress. Such electrical overstress events can include electrostatic discharge (ESD) events, such as field-induced charged-device model (FICDM) events, as well as other types of overstress conditions.

In examples, a system includes a differential input device having a first input and a second input. The system includes a window generator configured to output, at a first output, a first voltage above a reference voltage and a second voltage, at a second output, below the reference voltage. The system includes a multiplexer coupled to the first output and the second output, the multiplexer configured to receive the first voltage, the second voltage, and an input voltage. The system includes a selector coupled to the multiplexer and configured to select the first voltage, the second voltage, or the input voltage based on a value of the input voltage, where the selector is configured to cause the multiplexer to provide the selected voltage to the first input of the differential input device, where a voltage source provides the reference voltage to the second input of the differential input device.

A transmitting and receiving device having a module (GSZ) with a configurable HF high-power amplifier (HPA) that includes a main power amplifier (DM) with a main amplifier core and at least one peak power amplifier (DP1) having an auxiliary amplifier core. A switching element connected to inputs of the main power amplifier and the at least one peak power amplifier is connected to a digital input signal divider (ET) having a plurality of outputs and an output combiner (C) is connected to outputs of the amplifier cores for the main power amplifier and the at least one peak power amplifier. A multi-harmonic transformation line (LAH) is connected at the amplifier core output of the main power amplifier and at the amplifier core output of the at least one peak power amplifier, and a circulator (Z1) is connected to the output of the output combiner or an impedance converter (AN1).

According to certain aspects, a chip includes a pad, a power amplifier, a transformer coupled between an output of the power amplifier and the pad, a transistor coupled between the transformer and a ground, and a first clamp circuit coupled between a gate of the transistor and a drain of the transistor.

A post driver includes an input pair circuit, a protection circuit, a common mode sensing circuit and an amplifier. The input pair circuit outputs a first signal through a first node and outputs a second signal through a second node according to a first input signal and a second input signal. The protection circuit provides the input pair circuit with voltage protection according to multiple first bias voltages and a second bias voltage, transmits the first signal to a first load to generate a first output signal, and transmits the second signal to a second load to generate a second output signal. The common mode sensing circuit senses a level of the first node and a level of the second node to generate a feedback signal. The amplifier generates the second bias voltage according to a reference signal and the feedback signal.

A method for reducing gain for audio amplification by an audio system having a tweeter channel, an optional midrange channel, and a woofer channel. Gain of the woofer channel is reduced simultaneously with reducing gain of the tweeter channel, both responsive to detecting the same instance of overloading (overdriving) the woofer channel. Other aspects are also described and claimed.

Circuits for protecting devices, such as gallium nitride (VcclGaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.