An amplifier system including a push-pull power amplifier having an input to receive a radio frequency (RF) input signal and an output, the push-pull power amplifier being configured to amplify the RF input signal and provide at the output an RF output signal that is an amplified version of the RF input signal, a switchable shunt capacitance switchably connected between a load-line connected to the output of the push-pull power amplifier and a reference potential, and a switch configured to selectively connect the switchable shunt capacitance to the reference potential and disconnect the switchable shunt capacitance from the reference potential to vary an impedance of load-line.

Methods and devices used in mobile receiver front end to support multiple paths and multiple frequency bands are described. The presented devices and methods provide benefits of scalability, frequency band agility, as well as size reduction by using one low noise amplifier per simultaneous outputs. Based on the disclosed teachings, variable gain amplification of multiband signals is also presented.

Power amplifier (PA) output memory neutralization is disclosed, using baseband input/output (I/O) capacitance current compensation. Radio frequency (RF) PAs experience I/O memory effects when used with envelope tracking supply modulation schemes. Envelope tracking supply modulation results in a nonlinear variation of the I/O capacitance. Traditional approaches compensate for such effects with a current provided by a bias circuit which is band-limited. This results in memory effects which distort the amplified signal, becoming more significant as the modulation bandwidth increases. An RF communications system according to embodiments disclosed herein mitigates such memory effects by compensating for the non-linear effect of the I/O capacitance in an RF PA.

An apparatus is disclosed for complementary variable gain amplification. In an example aspect, the apparatus includes a variable gain amplifier that includes multiple amplifiers. The multiple amplifiers include at least one first amplifier and at least one second amplifier cascaded together in series. The first amplifier includes a first set of transistors having a first doping type. At least a portion of the first set of transistors is configured to implement a first current mirror. The second amplifier includes a second set of transistors having a second doping type. At least a portion of the second set of transistors is configured to implement a second current mirror. The second current mirror is coupled to the first current mirror.

A transistor circuit includes a transistor having a gate terminal and first and second conduction terminals, a first circuit configured to convert an AC input signal of the transistor circuit to a gate bias voltage and to apply the gate bias voltage to the gate terminal of the transistor, a second circuit configured to convert the AC input signal of the transistor circuit to a control voltage, and a switching circuit configured to apply a first voltage to the first conduction terminal of the transistor in response to the control voltage.

A semiconductor integrated circuit device includes a first terminal arranged to accept an external input of an analog input signal, an amplifier configured to amplify the analog input signal to generate an amplified signal, a logic unit configured to generate a digital output signal that is in accordance with the amplified signal, and a second terminal arranged to externally output an analog output signal that is in accordance with the amplified signal. The first terminal is disposed at a first side of a package, and the second terminal is disposed at a second side which is different from the first side.

Reducing a sensitivity of an electromechanical sensor is presented herein. The electromechanical sensor comprises a sensitivity with respect to a variation of a mechanical-to-electrical gain of a sense element of the electromechanical sensor; and a voltage-to-voltage converter component that minimizes the sensitivity by coupling, via a defined feedback capacitance, a positive feedback voltage to a sense electrode of the sense elementthe sense element electrically coupled to an input of the voltage-to-voltage converter component. In one example, the voltage-to-voltage converter component minimizes the sensitivity by maintaining, via the defined feedback capacitance, a constant charge at the sense electrode. In another example, the electromechanical sensor comprises a capacitive sense element comprising a first node comprising the sense electrode. Further, a bias voltage component can apply a bias voltage to a second node of the electromechanical sensor. In yet another example, the electromechanical sensor comprises a piezoelectric sense element.

A control circuit and method for a voltage converter. The control circuit having a ramp circuit, a reference generating circuit, a comparison circuit and a logic circuit. The ramp circuit generates a ramp signal that decreases from the moment the power switch is turned off and increases from the moment the power switch is turned on. The reference generating circuit generates a reference voltage. The comparison circuit compares the reference voltage with the sum of the feedback voltage and the ramp signal to generate a comparison signal. The logic circuit uses the comparison signal and a clock signal to generate the control signal to control a power switch of the voltage converter.

A power amplifier includes a two-dimensional matrix of NM active cells formed by stacking main terminals of multiple active cells in series. The stacks are coupled in parallel to form the two-dimensional matrix. The power amplifier includes a driver structure to coordinate the driving of the active cells so that the effective output power of the two-dimensional matrix is approximately NM the output power of each of the active cells.

An electronic device for detecting the weight of a capsule for a pharmaceutical product is provided with: a plurality of detection electrodes, which face a respective one of a plurality of sectors into which the capsule is divided in a main extension direction thereof, each one of the detection electrodes forming a respective detection capacitor with a common plate defined by a capsule-holding element which holds the capsule; and an electronic circuit having a plurality of detection stages, each operatively coupled to a respective one of the detection electrodes so as to detect, in an independent and exclusive manner, a capacitive variation of the respective detection capacitor and to generate a respective output quantity, which is a function of the capacitive variation and indicative of the weight of the respective sector of the capsule.