Low-leakage switch circuit techniques to reduce leakage current of an off-state switch, while maintaining a low on-resistance. The low-leakage switch circuit may allow measurement of low current signals in a transimpedance amplifier with improved accuracy without, the need for calibration. The low-leakage switch circuit may include a bootstrapping path connecting two or more terminals or voltage nodes of an off-state switch in the switch circuit. The bootstrapping path is configured to bootstrap major leakage current contributors in the switch circuit, such as the substrate diode leakage, the subthreshold leakage, or combinations thereof.

The present disclosure is to improve the power added efficiency of a power amplifier at high output power. The power amplifier includes: a first capacitor with a radio frequency signal input to one end thereof; a first transistor whose base is connected to the other end of the first capacitor to amplify the radio frequency signal; a bias circuit for supplying bias to the base of the first transistor; and a second capacitor with one end connected to the base of the first transistor and the other end connected to the emitter of the first transistor.

Measurement of signal power for variable or time varying signals. A log-linear VGA coupled in a feedback configuration to a difference detector and an integrator, includes a set of amplifier cells selectable by a sliding current generator, producing a sum of outputs. Outputs of the sliding current generator include a first control current provided using a sum of amplified currents, a sequence of intermediate control currents, and a final control current provided using a sum of amplified currents. Control currents to be summed can be differentially amplified or attenuated; attenuators include capacitors to compensate for capacitive loading. Selectable amplifier cells are differentially amplified or attenuated. Isolating switches and canceling stages reduce the effects of leakage between adjacent amplifier cells. The sliding current generator can have boosted current to first and last amplifier cells, providing a more linear-in-dB gain near a relative maximum or minimum.

Techniques are disclosed to allow for a switched capacitor digital power amplifier (PA) that operates using high supply voltage levels beyond twice the maximum voltage rating for any of the transistor terminals such as Vds/Vdg/Vsg.

A monolithic integrated circuit (IC), and method of manufacturing same, that includes all RF front end or transceiver elements for a portable communication device, including a power amplifier (PA), a matching, coupling and filtering network, and an antenna switch to couple the conditioned PA signal to an antenna. An output signal sensor senses at least a voltage amplitude of the signal switched by the antenna switch, and signals a PA control circuit to limit PA output power in response to excessive values of sensed output. Stacks of multiple FETs in series to operate as a switching device may be used for implementation of the RF front end, and the method and apparatus of such stacks are claimed as subcombinations. An iClass PA architecture is described that dissipatively terminates unwanted harmonics of the PA output signal. A preferred embodiment of the RF transceiver IC includes two distinct PA circuits, two distinct receive signal amplifier circuits, and a four-way antenna switch to selectably couple a single antenna connection to any one of the four circuits.

It is disclosed an amplifier for driving a capacitive load, comprising an input terminal adapted to receive an input voltage signal, an output terminal adapted to drive the capacitive load, a linear amplification stage, switching amplification stage, a capacitor, a first switch and a measurement and control circuit. The measurement and control circuit is configured to: measure the value of the current generated at the output from the linear amplification stage and generate a driving voltage signal of the switching amplification stage; generate the first switching signal to open the first switch and generate an enabling signal to enable the operation of at least part of the switching amplification stage; generate the first switching signal to close the first switch and generate the enabling signal to disable the operation of the switching amplification stage; generate the first switching signal to open the first switch.

A semiconductor amplifier 1 includes transistors 21a and 21b mounted side by side on a bottom plate 2 in a space in a package 6, a matching circuit 22a mounted between the transistors 21a, 21b on the bottom plate 2, a matching circuit 22b mounted on an opposite side of the transistor 21b from the transistor 21a on the bottom plate 2, an input terminal T.sub.IN installed on one side of a wiring substrate 3, an output terminal T.sub.OUT installed on the other side of the wiring substrate 3, and gate bias terminals T.sub.1G and T.sub.2G and drain bias terminals T.sub.1D and T.sub.2D installed at positions with the input terminal T.sub.IN and the output terminal T.sub.OUT of the wiring substrate 3, and the transistor 21a, the matching circuit 22a, the transistor 21b, and the matching circuit 22b are linearly placed between the input terminal T.sub.IN and the output terminal T.sub.OUT.

A radio frequency front-end is disclosed having a first power amplifier (PA) having a first PA input and a first PA output, a second PA having a second PA input and a second PA output, and a low-noise amplifier (LNA) having an LNA output connected to a receive output terminal and an LNA input. An input 90° hybrid coupler has a first port input connected to a transmit terminal, a second port input connected to a fixed voltage node through an isolation impedance, a third port output connected to the first amplifier input and a fourth port output connected to the second amplifier input. An output 90° hybrid coupler has a first port output connected to a common terminal, a second port output connected to the LNA input, a third port input connected to the second PA output, and a fourth port input connected to the first PA output.

According to an embodiment, An integrated circuit comprising a first cascode radio frequency (RF) power amplifier that includes a first common source transistor having a gate configured to receive a first RF signal, and a source connected to a neutral point; a first common gate transistor having a gate and a drain connected to a power source node, and a source connected to a drain of the first common source transistor; and a first resistor coupled between a bulk of the first common gate transistor and a first bulk bias node configured to provide a voltage that is greater than or equal to a voltage at the source of the first common gate transistor, wherein the first resistor is configured to obtain a floating point.

A system for adjusting various parameters of an active electronic component based on sensed characteristics of the active electronic component and/or characteristics of the input or output power.