A semiconductor device includes a plurality of unit cell transistors on a common semiconductor structure, the unit cell transistors electrically connected in parallel, and each unit cell transistor including a respective gate finger. Respective threshold voltages of first and second of the unit cell transistors differ by at least 0.1 volts and/or threshold voltages of first and second segments of a third of the unit cell transistors differ by at least 0.1 volts.

A semiconductor device includes a plurality of unit cell transistors on a common semiconductor structure, the unit cell transistors electrically connected in parallel, and each unit cell transistor including a respective gate finger. Respective threshold voltages of first and second of the unit cell transistors differ by at least 0.1 volts and/or threshold voltages of first and second segments of a third of the unit cell transistors differ by at least 0.1 volts.

An amplifier arrangement has a first differential stage with a first transistor pair, a second differential stage with a first and a second transistor pair, each pair having a common source connection. The amplifier arrangement further has a first complementary differential stage with a transistor pair having opposite conductivity type, and a second complementary differential stage with a first and a second transistor pair of the complementary conductivity type. The first and the second complementary differential stage are connected symmetrically compared to the first and the second differential stage. The transistors of the second differential stage and the second complementary differential stage are symmetrically connected to form respective first, second, third and fourth current paths. A pair of output terminals is coupled to the first and the fourth current path. Gate terminals of the transistors are coupled to a respective pair of input terminals.

In an apparatus for multi-pole acoustic logging while drilling, a N-cycle sinusoidal wave signal is generated by utilizing a signal processor, and amplified into a high-voltage sinusoidal excitation signal by utilizing a power amplifier, and output to a transmitting transducer. The signal processor simultaneously generates an enable signal. The enable signal includes a transient discharge enable signal. The power amplifier is connected with a transient discharge circuit. After the signal processor generates N cycles of a sinusoidal wave, the transient discharge enable signal enables the transient discharge circuit to discharge to release an energy storage current of a power transformer so as to eliminate a high-voltage ringing effect and improve an excitation efficiency of the transducer.

A radiofrequency (RF) amplifier includes an input terminal, an output terminal, and a power supply and biasing stage having an output coupled to the input terminal. An amplification stage of the RF amplifier includes a first transistor having a control terminal coupled to the input terminal and a first conduction terminal coupled to the output terminal. The power supply and biasing stage is configured to generate a bias voltage at the control terminal of the first transistor to simultaneously regulate a power supply voltage of the amplification stage to a first voltage and a bias current of the amplification stage to a first current.

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.

A linear power source circuit includes: an input unit to which an input signal is input and which outputs a first current signal; a current-voltage convertor which converts the first current signal into a first voltage signal; a voltage-current convertor configured to convert the first voltage signal into a second current signal; and an output unit configured to generate an output voltage signal from the second current signal by a first current mirror unit, a second current mirror unit, and a third current mirror unit, and configured to output the output voltage signal to an output terminal. The input unit and the current-voltage convertor constitute a current feedback type operational amplifier.