A voltage detection circuit including an input voltage stage configured to scale down an input voltage to produce a scaled down voltage, a gain loss stage configured to receive and adjust the scaled down voltage based on a determined gain or loss to be applied to the scaled down voltage, and a comparison circuit configured to determine if the input voltage is over or under a desired voltage value.

A broadband amplifier assembly is provided that includes a fixed gain amplifier coupled to an adjustable attenuator which is further coupled to a power amplifier. The adjustable attenuator includes a plurality of attenuation cells directly coupled in series between the input and the output of the adjustable attenuator.

In conventional optical receivers the dynamic range is obtained by using variable gain amplifiers (VGA) with a fixed trans-impedance amplifier (TIA) gain. To overcome the SNR problems inherent in conventional receivers an improved optical receiver comprises an automatic gain control loop for generating at least one gain control signal for controlling gain of both the VGA and the TIA. Ideally, both the resistance and the gain of the TIA are controlled by a gain control signal.

An amplifier includes an amplification circuit, an equalization circuit, an output circuit, a first gain adjusting circuit, and a second gain adjusting circuit. The amplification circuit changes voltage levels of first and second amplification nodes based on first and second input signals. The equalization circuit changes the voltage levels of the first and second amplification nodes. The output circuit generates an output signal based on the voltage levels of the first and second amplification nodes. The first gain adjusting circuit changes voltage levels applied to the first and second amplification nodes based on the voltage levels of the first and second amplification nodes and a first gain control signal. The second gain adjusting circuit changes a voltage level of the output signal based on a second gain control signal.

In electronic circuits having various gain states, small gain phase shift differences required among various gain states may pose a challenging problem. The disclosed methods and devices provide solution to such challenge. Electronic circuits are described wherein a first path including an amplifier may be bypassed by a second path including only passive elements and for gain states smaller than 0 dB. In such electronic circuits, a phase shifter included in the second path can be adjusted to address the required phase shift among various gain states.

A light receiving unit receives a pulsed optical signal arriving from a search region. A branching unit generates, from a received light signal, a plurality of branch signals having signal intensities proportional to a signal intensity of the received light signal and different from one another. A conversion unit converts, from analog to digital, a signal fed via the individual path selected by a selection unit, and in accordance with a result of the conversion, a processing unit generates information regarding an object reflecting the optical signal. A control unit causes the selection unit to select one of the individual paths for which a determination unit determines that a magnitude of the fed signal is within an input range of the conversion unit and which provides the highest gain.

The disclosed technology is related to a radio-frequency (RF) amplifier having a bypass circuit and a resonant structure to improve performance in a bypass mode (e.g., a low gain mode). The disclosed amplifiers have a resonant structure that effectively isolates an amplifier core from a bypass circuit. For example, in a bypass mode, the resonant structure is configured to create an open impedance looking into the amplifier core input. This effectively removes any loading from the amplifier core to the bypass circuit. The disclosed amplifiers with resonant structures improve linearity performance in bypass modes due at least in part to the open impedance to the amplifier core provided by the resonant structure.

A matching circuit comprising: an input-terminal configured to be connected to an active-circuit; an output-terminal configured to be connected to a downstream component; a current-source configured to provide a disabled-current; one or more diode-modules, each comprising a diode and a biasing-resistor in parallel with each other; and a reactive-matching-component that has a reactive impedance. The current source is configured to pass the disabled-current through the one or more diode-modules and the reactive-matching-component when the matching circuit is in a disabled-mode of operation such that they contribute to the impedance of the matching circuit between the input-terminal and the output-terminal.

An instrumentation amplifier configured for providing high common mode rejection is described and includes an input differential stage configured to receive a differential input voltage and a folded cascode amplifying stage configured to receive output current mode signals provided from the input differential pair. A plurality of feedback networks is provided to improve the input stage. The amplifier may operate to provide an enhanced common mode rejection ratio of a single gain block in the instrumentation amplifier. In some examples, the circuitry may have a differential folded cascode amplifying stage which permits high precision and low distortion of amplified signals without degrading the common mode rejection ratio.

An amplifier circuit includes: an input circuit configured to receive an input signal; a load circuit provided in series with the input circuit and including a first variable resistance unit and a second variable resistance unit, a resistance value of the first variable resistance unit being controlled by a digital code, a resistance value of the second variable resistance unit being controlled by an analog control voltage; and a correction circuit including a third variable resistance unit having a circuit configuration corresponding to the first variable resistance unit and a fourth variable resistance unit having a circuit configuration corresponding to the second resistance unit, a resistance value of the third variable resistance unit being controlled by the digital code, a resistance value of the fourth variable resistance unit being controlled by the analog control voltage, the correction circuit being configured correct a resistance value of the load circuit.