A Programmable-Gain Amplifier (PGA) has programming steps that are linear when expressed in Decibels (linear-in-dB). A Recursive Current Division (RCD) resistor network generates currents that are selected by programmable switches to connect to a summing node input of an amplifier. A feedback resistor is connected across the summing node and the amplifier output. The resistor network has only three resistance values regardless of the number of currents selectable as programming steps. The value of a third resistor is set equal to the equivalent resistance of a second resistor in parallel with a series connection of a first resistor and the third resistors. Each final cell in the resistor network is equivalent to the third resistor, allowing recursive division of adjacent currents. The ratio of adjacent currents remains constant for all cells. Recursive Current Division (RCD) produces linear-in-dB programming steps. Floating switches are avoided since switches connect to ground.

In an incore nuclear instrumentation system which is equipped with a movable type neutron detector, an object of the invention is to control measurement errors due to the degradation of the system. The incore nuclear instrumentation system includes a neutron detector which is to be installed in a nuclear reactor stored in a containment vessel, and an instrumentation unit which has a current detector circuit and is to be installed on the outside of the containment vessel. An output signal of the neutron detector is inputted into the current detector circuit, and the instrumentation unit remembers a matrix which shows a relation among a reactor power of the nuclear reactor, a gain of the current detector circuit, and an output voltage Vn of the current detector circuit, and the calibration of the current detector circuit is performed with reference to the matrix.

A differential amplifier generates an output voltage waveform exhibiting a slew rate over a rise time. The amplifier is powered from a dc voltage input and includes a set of differential pairs having a bias current flowing therethrough and a Miller compensation capacitance. A comparator functions to compare a voltage at the dc voltage input against a reference voltage in order to detect when the voltage drops below the reference voltage. A gain stage controls the gain of the differential amplifier and a bias current control circuit controls the bias current of the differential amplifier. In response to the detection by the comparator of the voltage dropping below the reference voltage, the gain stage and the bias current control circuit decrease the gain of the amplifier and jointly decrease the bias current in order to maintain a value of the rise time.

A multi-mode multi-band power amplifier includes a controller, a wide-band amplifier channel and a fundamental impedance transformer. The controller receives an external signal and outputs a control signal according to the external signal. The wide-band amplifier channel receives single-band or multi-band RF signals through the input terminal, performs power amplification on the RF signals and outputs the RF signals through the output terminal. The fundamental impedance transformer includes a first segment shared by RF signals in all bands, second segments respectively special for RF signals in all bands, and a switching circuit controlled by the controller to separate RF signals subject to power amplification to the second segment in a switchable manner for multiplexed outputs.

An inverter includes a positive electrode terminal and a negative electrode terminal, upper-arm switching elements and lower-arm switching elements, and a voltage divider that supplies partial voltages of a voltage between the positive electrode terminal and the negative electrode terminal to a gate and a drain, respectively, of the lower-arm switching element. The lower-arm switching element includes an HEMT. In the voltage divider, the partial voltages are set to turn the lower-arm switching element off when a positive electrode and a negative electrode of a DC power supply are reversely connected to the positive electrode terminal and the negative electrode terminal, respectively.

A comparator can incorporate a hysteresis circuit to control when the output of the comparator changes between a high voltage signal and a low voltage signal. The comparator can receive a differential signal and can output either the high voltage signal or the low voltage signal. When the differential input signal is above a first threshold voltage, the output of the comparator can transition to the high voltage signal and when the differential input signal is below a second threshold voltage, the output of the comparator can transition to the low voltage signal. The hysteresis circuit of the comparator is used to adjust the first threshold voltage and the second threshold voltage required to transition the output of the comparator based on the present state of the output signal of the comparator.

A power amplification module includes a first input terminal that receives a first transmit signal in a first frequency band, a second input terminal that receives a second transmit signal in a second frequency band having a narrower transmit/receive frequency interval than the first frequency band, a first amplification circuit that receives and amplifies the first transmit signal to produce a first amplified signal and outputs the first amplified signal, a second amplification circuit that receives and amplifies the second transmit signal to produce a second amplified signal and outputs the second amplified signal, a third amplification circuit that receives and amplifies the first or second amplified signal to produce an output signal and outputs the output signal, and an attenuation circuit located between the second input terminal and the second amplification circuit and configured to attenuate a receive frequency band component of the second frequency band.

A differential amplification circuit includes: a first transistor and a second transistor of a differential pair; first and second loads; current sources; and a resistor circuit, wherein the resistor circuit includes: a coarse adjustment part and a fine adjustment part, one of the coarse adjustment part and the fine adjustment part includes a first lateral adjustment part and a second lateral adjustment part which have the same configuration, the first lateral adjustment part and the second lateral adjustment part are connected symmetrically to both sides of a central adjustment part, and the central adjustment part has a circuit configuration symmetrical with respect to two connection nodes with the first lateral adjustment part and the second lateral adjustment part.

At least some embodiments are directed to a system comprising an amplifier containing a first bias current source and configured to provide an output voltage at a node, a gain stage coupled to the node and comprising a second bias current source, and a buffer stage coupled to the node and comprising third and fourth bias current sources and an additional set of bias current sources, the third and fourth bias current sources are able to activate output transistors that are configured to increase current provided to a load. The system also comprises a controller configured to activate the first bias current source, to activate the second bias current source after the first bias current source is activated, to activate the bias current sources in the set after the first bias current source is activated, and to activate the third and fourth bias current sources after the first and second bias current sources are activated and after the bias current sources in the set are activated.

Provided is an amplification circuit that amplifies an input signal and outputs an amplified signal. The amplification circuit includes: an amplification element that outputs the amplified signal from an output terminal thereof; an inductor having one end to which a power supply voltage is supplied and another end that is connected to the output terminal of the amplification element; a variable resistor that is connected in parallel with the inductor; and a resistance value adjusting circuit that adjusts a resistance value of the variable resistor in accordance with the temperature.