An ultrasound probe buffer is provided. The ultrasound probe buffer may include a high impedance amplifier having a common-source core stage with series-series local feedback. The high impedance amplifier may include a first MOSFET and a second MOSFET, wherein a source terminal of the first MOSFET is coupled to a source terminal of the second MOSFET.

A method is used for operating a switching amplifier, the switching amplifier includes a plurality of cascade elements. The method includes: coupling the cascade elements in series between two terminals of a load; providing two leg circuits each comprised of switches in each of the cascade elements; and controlling all of the switches comprised in the switching amplifier using space vector modulation (SVM), such that a change of a common mode (CM) voltage generated by the switching amplifier is in a predetermined range.

In a preamplifier (amplifier) for the radiation detector, an interconnection layer connected to the bonding pad forms one electrode of a feedback capacitor. Since there is no wiring for connecting the bonding pad and capacitor, a parasitic capacitance caused by the wiring will not be generated. Moreover, the capacitor is arranged below the bonding pad with a conductive layer serving as the other electrode, so that the feedback capacitance of the capacitor is included in the parasitic capacitance between the interconnection layer and the substrate. Compared to the conventional case, an amount of capacitance corresponding to the parasitic capacitance caused by wiring and the feedback capacitance for the capacitor is reduced from the input capacitance. Thus, the input capacitance for the amplifying circuit is reduced.

Transconductor circuits with programmable tradeoff between bandwidth and flicker noise are disclosed. An example circuit includes an input port, an output port, a plurality of transistors, and a switch arrangement that includes a plurality of switches, configured to change coupling between the input port, the output port, and the transistors to place the transconductor circuit in a first or a second mode of operation. An input capacitance of the transconductor circuit operating in the first mode is larger than when the transconductor circuit is operating in the second mode. In the first mode, having a larger input capacitance results in a decreased flicker noise because the amount of flicker noise is inversely proportional to the input capacitance. In the second mode, having a smaller input capacitance leads to an increased flicker noise but that is acceptable for wide-bandwidth applications because wide-bandwidth signals may be less sensitive to flicker noise.

A differential signal input buffer is disclosed. The differential signal input buffer may receive a differential signal that includes a first signal and a second signal and may be divided into a first section and a second section and. The first section may buffer and/or amplify the first signal based on a first level-shifted second signal. The second section may buffer and/or amplify the second signal based on a first level-shifted first signal. In some implementations, the first section may buffer and/or amplify the first signal based on a second level-shifted second signal. Further, in some implementations, the second section may buffer and/or amplify the second signal based on a second level-shifted first signal.

It is described a charge preamplifier device (100) integrated in a chip (200) of semiconductive material comprising: an input (IN) for an input signal (i.sub.IN) and an output (OUT) for an output signal (v.sub.OUT); a substrate (202) of semiconductive material doped according to a first type of conductivity; an electrically insulating layer (204) placed on said substrate (202); a feedback capacitor (C.sub.f) integrated in the chip (200) and comprising a first electrode (3) connected to the input (IN) and a second electrode (2) connected to the output (OUT). The second electrode (2) is formed by a doped conductive region (205) having a second type of conductivity, opposite to the first type of conductivity, and integrated in the substrate (202) in order to face the first electrode (3).

An amplifier includes a first capacitor connected between an input node and a floating node, a second capacitor connected between the floating node and an output node, an amplifying element connected between a power supply voltage and the output node and operating in response to a voltage level of the floating node, a current bias source connected between the output node and a ground voltage, a first reset switch connected between the floating node and an intermediate node and operating in response to a reset bias, a second reset switch connected between the intermediate node and the output node and operating in response to the reset bias, and a reset bias generator circuit that outputs the reset bias in response to a reset signal. The reset bias is one of a reset voltage of the intermediate node, the power supply voltage, and the ground voltage.

A sensor assembly including a capacitive sensor, like a microelectromechanical (MEMS) microphone, and an electrical circuit therefor are disclosed. The electrical circuit includes a first transistor having an input gate connectable to the capacitive sensor, a second transistor having an input gate coupled to an output of the first transistor, a feedforward circuit interconnecting a back-gate of the second transistor and the output of the first transistor, and a filter circuit interconnecting the output of the first transistor and the input gate of the second transistor.

A package (1) includes first and second input terminals (2,3) which are adjacent to each other, and first and second output terminals (4,5) which are adjacent to each other. A first input matching circuit (6), a first delay circuit (7), a second input matching circuit (8), a first amplifier (9), and a first output matching circuit (10) are sequentially connected between the first input terminal (2) and the first output terminal (4) inside the package (1). A third input matching circuit (11), a second amplifier (12), a second output matching circuit (13), a second delay circuit (14), and a third output matching circuit (15) are sequentially connected between the second input terminal (3) and the second output terminal (5) inside the package (1). First to fourth matching circuits (16-19) are respectively connected to the first input terminal (2), the second input terminal (3), the first output terminal (4) and the second output terminal (5) outside the package (1).

Compact low noise amplifiers that have wide-band coverage while meeting necessary input matching and output matching characteristics. Embodiments include a wide-band, two-stage LNA with minimum degradation in performance compared to multiple narrow-band, single-stage LNAs. A generalized embodiment includes a first amplifier stage having a terminal coupled to a mutually coupled inductor circuit and to a second amplifier stage. The second amplifier stage includes a terminal coupled to the mutually coupled inductor circuit. The mutually coupled inductor circuit comprises electromagnetically coupled inductors L1, L2. Second terminals of the first and second amplifier stages are coupled to respective degeneration inductors. The electromagnetically coupled inductors L1, L2 of the inductor circuit substantially increase the output bandwidth of the LNA with minimum degradation in performance.