A balanced differential transimpedance amplifier with a single-ended input operational over a wide variation in the dynamic range of input signals. A threshold circuit is employed to either or a combination of (1) generate a varying decision threshold to ensure a proper slicing over a wide range of input current signal levels; and (2) generate a bias current and voltage applied to an input of a transimpedance stage to cancel out a dependence of the transimpedance stage voltage input on input current signal levels.

Provided is an emphasis circuit capable of obtaining a desired emphasis amount with which waveform deterioration of an output signal in a high frequency band (high frequency band deterioration) is suppressed without increasing power consumption (current consumption). In the emphasis circuit, a baseband amplifier section and a peaking amplifier section are connected in parallel to each other, and respective drive current setting sections are adjusted to adjust respective drive current values thereof so that the sum of the drive current value of the baseband amplifier section and the drive current value of the peaking amplifier section may be constant.

A circuit includes a first transconductance stage having an output. The circuit further includes an output transconductance stage, and a first source-degenerated transistor having a first control input and first and second current terminals. The first control input is coupled to the output of the first transconductance stage. The circuit also includes a second transistor having a second control input and third and fourth current terminals. The third current terminal is coupled to the second current terminal and to the output transconductance stage.

A squelch detection device is provided. The squelch detection device receives first and second input signals and first and second threshold voltages. The squelch detection device determines a first common mode of the first and second input signals and a second common mode of the first and second threshold voltages. The squelch detection device averages the first common mode with the second common mode to produce an average common mode and sets the first common mode of the first and second input signals to the average common mode. The squelch detection device sets the second common mode of the first and second threshold voltages to the average common mode and determines a state of a squelch signal, indicative of whether the first and second input signals are attributable to noise, based on the first and second input signals and the first and second threshold voltages.

A squelch detection device is provided. The squelch detection device receives first and second input signals and first and second threshold voltages. The squelch detection device determines a first common mode of the first and second input signals and a second common mode of the first and second threshold voltages. The squelch detection device averages the first common mode with the second common mode to produce an average common mode and sets the first common mode of the first and second input signals to the average common mode. The squelch detection device sets the second common mode of the first and second threshold voltages to the average common mode and determines a state of a squelch signal, indicative of whether the first and second input signals are attributable to noise, based on the first and second input signals and the first and second threshold voltages.

In a differential amplifier circuit, a differential amplifier circuit unit includes: first and second transistors provided between a current source circuit and a load circuit, which receives differential input signals at gates to generate differential output signals at drains; and a third transistor connected between sources of the first and second transistors, which receives a control signal at a gate. A replica amplifier circuit unit includes: a voltage generation circuit which generates first and second reference voltages; first and second replica transistors which receives the first and second reference voltages at gates to generate replica output signals at drains; a third replica transistor connected between sources of the first and second replica transistors, which receives the control signal at a gate; and an operational amplifier which generates the control signal according to a difference between at least one of the first and second reference voltages and the replica output signal.

A variable-gain amplifier includes two amplification and attenuation branches, and first and a second resistive elements that are coupled between the two branches. Each branch includes a voltage follower stage and a configurable amplification stage. The voltage follower stages are intended to receive a differential signal and are configured to deliver, via the first resistive element, an intermediate differential current signal. The amplification stages are intended to receive the intermediate differential current signal and a digital control word, and are configured to deliver, via the second resistive element, an output differential voltage signal depending on the value of the digital control word.

A circuit includes a first transconductance stage having an output. The circuit further includes an output transconductance stage, and a first source-degenerated transistor having a first control input and first and second current terminals. The first control input is coupled to the output of the first transconductance stage. The circuit also includes a second transistor having a second control input and third and fourth current terminals. The third current terminal is coupled to the second current terminal and to the output transconductance stage.

An electronic circuit for a micro-electro-mechanical systems gyroscope is disclosed. The electronic circuit includes a current buffer, a transimpedance amplifier coupled with the current buffer, and a plurality of transistors. An inverting input terminal of the current buffer and a non-inverting input terminal of the current buffer are connected with a plurality of first resistors. The inverting input terminal of the current buffer is connected with a source of one of the plurality of transistors, and the non-inverting input terminal of the current buffer is connected with a source of another one of the plurality of transistors. The plurality of first resistors are connected to a ground. The current buffer is configured to isolate a load in the micro-electro-mechanical systems gyroscope from the transimpedance amplifier.

A circuit (200) for testing failure of a connection between a radio frequency, RF, integrated circuit (201) and external circuitry (204), the circuit comprising: an amplifier (205) having first and second input paths (215, 216) and first and second output paths (206, 207); a first power detector (208, 209) coupled to one of said first or second output paths; at least one connection (211) between said first and second output paths (206, 207) and said external circuitry (204), connecting said outputs to a RF combiner (210) said external circuitry; at least one disabling circuit (230, 232, 234, 236, 240, 242, 260, 262) coupled to at least one of said first and second output paths (206, 207) or at least one of said first and second input path (215, 216), before said path reaches said power detector (208, 209); for disabling one of said inputs or outputs; wherein when said input or output path is disabled (206, 207), and a signal is output along the enabled output path (206, 207), the power detector (208, 209) on said disabled output path can detect if there is a failure in said at least one connection (211).