Abstract: A switch-around low noise amplifier (LNA) device includes an input for receiving an input signal; an output for outputting an output signal; an LNA transistor coupled between the input and the output; a bypass switch circuit coupled between the input and the output; a current mirror circuit operatively connected to the LNA transistor to control a current flowing through the LNA transistor; a source follower switch operatively connected to the current mirror circuit to selectively turn on and off the current through the current mirror circuit in response to a mode select signal; and a driver adapted to selectively turn on and off the bypass switch circuit in response to the mode select signal. The LNA transistor receives the input signal at its control terminal, and one of the first and second terminals is directly connected to a supply voltage (e.g., ground).

Abstract: A four-state digital attenuator for an RF signal includes a first external terminal adapted to receive a first control voltage; a second external terminal adapted to receive a second control voltage, and a third external terminal connected to a fixed supply voltage. The four-state digital attenuator receives no supply voltages other than the control voltages and the fixed supply voltage connected to the third external terminal. A plurality of series paths are provided from an RF input to an RF output, each of the series paths passing through a node. A plurality of shunt paths are provided from the node to the third external terminal. A driver selectively enables the series paths and shunt paths in response to the first and second control voltages to provide four attenuation levels for an RF signal from the RF input to the RF output.

Abstract: A mixer includes a first field effect transistor (FET) having a gate that receives a first signal of a balanced local oscillator (LO) signal, a first source/drain coupled to a ground voltage, and a second source/drain; and a second FET having a gate that receives a second signal of the balanced LO signal, a first source/drain that floats, and a second source/drain connected to the second source/drain of the first FET to form a mixing node, the second signal being out of phase with the first signal. A diplexer is connected between the mixing node and each of a radio frequency (RF) port and an intermediate frequency (IF) port. A first LO leakage caused by the first FET is substantially canceled by a second LO leakage caused by the second FET at the mixing node.

Abstract: An apparatus includes an input-bias node and an internal load. The input-bias node is configured to simultaneously receive an input signal and a bias signal through an input-bias port. The internal load is connected between the input-bias node and multiple output ports, at least one of the output ports outputting an output signal based on the input signal received at the input-bias node.

Abstract: An apparatus for setting an attenuation of an attenuator includes a control transistor, which includes a drain connected to a gate of a shunt transistor of the attenuator. A channel resistance of the shunt transistor corresponds to a current density of the control transistor, and the channel resistance of the shunt transistor determines the attenuation of the attenuator. The current density of the control transistor is based at least in part on a control voltage input to the apparatus.

Abstract: A mixer includes a first field effect transistor (FET) having a gate that receives a first signal of a balanced local oscillator (LO) signal, a first source/drain coupled to a ground voltage, and a second source/drain; and a second FET having a gate that receives a second signal of the balanced LO signal, a first source/drain that floats, and a second source/drain connected to the second source/drain of the first FET to form a mixing node, the second signal being out of phase with the first signal. A diplexer is connected between the mixing node and each of a radio frequency (RF) port and an intermediate frequency (IF) port. A first LO leakage caused by the first FET is substantially canceled by a second LO leakage caused by the second FET at the mixing node.

Abstract: An electrical circuit having improved linearity across a desired attenuation range includes a shunt circuit having a first field effect transistor (FET) adapted to couple a first signal-carrying electrical node of the electrical circuit to a ground node

Abstract: An electrical circuit having improved linearity includes a resistive circuit having a plurality of field effect transistors (FETs) and one or more gate biasing circuits.

Abstract: The apparatus includes a series active continuous time voltage regulator operating in conjunction with a alternating current power source and one or more loads. The alternating current power source is a voltage source that induces currents at a first end of the apparatus. At a second end of the apparatus one or more loads consume power from the apparatus. The series buck-boost regulator is composed of a pure monochromatic voltage source of frequency equal to that of the alternating current power source, and of constant phase with respect to the alternating current power source. The regulator is further composed of a sampling network that provides a scaled continuous time sample of the voltage delivered by the power conditioner to the loads. Finally, the regulator is composed of a high gain differential amplifier.

Abstract: A switching system includes a first transistor having a first gate and coupled between a first terminal and a second terminal and a second transistor having a second gate and coupled between the second terminal and a third terminal. The first transistor and the second transistor are configured to conduct a signal current between the first terminal and the third terminal. An impedance component coupled to the first gate and the second gate is configured to isolate a first gate signal voltage at the first gate or isolate a second gate signal voltage at the second gate to reduce a distortion of the signal current.

Abstract: A transmission line balun eliminates unwanted reflection of signal energy coupling to a ground plane. A junction of the conductive segments connected to the unbalanced port on the balun is connected to the ground plane with a resistor. The selected junction is a virtual ground of the balun, so the presence of the resistor does not degrade the balun performance. The resistor dissipates the energy from the parasitic mode propagating with the ground plane so that no signal is reflected back to short out the signal source. The value of the resistor is selected to facilitate maximum termination of the parasitic mode propagation.

Abstract: A transmission line balun eliminates unwanted reflection of signal energy coupling to a ground plane. A junction of the conductive segments connected to the unbalanced port on the balun is connected to the ground plane with a resistor. The selected junction is a virtual ground of the balun, so the presence of the resistor does not degrade the balun performance. The resistor dissipates the energy from the parasitic mode propagating with the ground plane so that no signal is reflected back to short out the signal source. The value of the resistor is selected to facilitate maximum termination of the parasitic mode propagation.

Abstract: A switching system includes a first transistor having a first gate and coupled between a first terminal and a second terminal and a second transistor having a second gate and coupled between the second terminal and a third terminal. The first transistor and the second transistor are configured to conduct a signal current between the first terminal and the third terminal. An impedance component coupled to the first gate and the second gate is configured to isolate a first gate signal voltage at the first gate or isolate a second gate signal voltage at the second gate to reduce a distortion of the signal current.

Abstract: An amplifier circuit includes an amplifier stage and a balun stage. The amplifier stage includes a common node connected to an external ground. An inductance is located between the common node and the external ground. The balun stage is connected to the amplifier stage. The balun stage includes a balun tail. The balun tail is directly connected to the common node of the amplifier stage so that a resulting connection between the balun tail and the common node bypasses the inductance between the common node and the external ground.

Abstract: The apparatus includes a series active continuous time voltage regulator operating in conjunction with a alternating current power source and one or more loads. The alternating current power source is a voltage source that induces currents at a first end of the apparatus. At a second end of the apparatus one or more loads consume power from the apparatus. The series buck-boost regulator is composed of a pure monochromatic voltage source of frequency equal to that of the alternating current power source, and of constant phase with respect to the alternating current power source. The regulator is further composed of a sampling network that provides a scaled continuous time sample of the voltage delivered by the power conditioner to the loads. Finally, the regulator is composed of a high gain differential amplifier.

Abstract: A mixing method and mixer structure provide a circuit topology suitable for use in radio receivers, transmitters, tuners, instrumentation systems, telemetry systems, and other systems and devices performing frequency conversion in either homodyne or heterodyne implementations. The inventive mixer may be used for wireless communication devices including radios, cellular telephones, and telemetry systems whether land, sea, airborne, or space based, and whether fixed or mobile. The mixer provides superior intermodulation and harmonic distortion suppression and features excellent conversion loss, noise figure, port match, and port isolation as a result of its circuit topology. The mixer device circuit combines the advantages of series mixing FETs, a triple balanced design using a balanced passive reflection transformer, a precise local oscillator phase splitter, and square wave gate drive having high slew rate signal characteristics to achieve high levels of performance.

Abstract: A radio comprising an FET mixing device for multiplying a first-frequency signal with a second frequency signal to generate a third frequency analog mixer output signal. A local oscillator input port receives a periodic sinusoidal local oscillator signal at a local oscillator frequency from an external local oscillator source. A drive circuit generates a substantially square-wave two-voltage level switching signal for driving said mixing device. An analog-to-digital converter generates a digital representation of said third frequency analog mixer output signal.

Abstract: A high dynamic range mixer apparatus and mixing method where a wide high dynamic range is achieved in part due to the use of a series pair of switching devices that are matched so as to afford complete or substantial cancellation of nonlinearity distortion. The inventive structure and method preserves the compensation and cancellation mechanism of the series pair of back-to-back connected FETs without the need for either of an intermediate frequency (IF) balun or a radio-frequency (RF) balun. Typically, the switching devices are PETs, such as for example MESFETs, connected source-to-source with one drain terminal grounded, and a non-grounded or floating switching signal applied between the common gate and common source terminals.

Abstract: A unbalanced mixer capable of operation in the absence of DC bias is disclosed herein. The mixer includes an input or local oscillator (LO) port for receiving an input signal. A first transistor has a control terminal coupled to the mixer input port, and an output terminal coupled to a first signal port of the mixer. The mixer further includes a resonator circuit, connected between the transistor control and output terminals, for providing signal isolation between the mixer input port and the first signal port. In a preferred implementation the resonator circuit comprises an inductive element in parallel with a first intrinsic capacitance of the transistor. The mixer may also include a diplexer circuit for coupling signal energy of a first frequency between the output terminal and the first signal port, and for coupling signal energy of a second frequency between the output terminal and a second signal port.