An attenuating device for a bus of a controller area network bus system based on differential voltage signals. The bus has first and second bus lines, having an attenuating circuit that provides a variable electrical resistance value between the first and second bus lines and that is operable in at least three circuit states. In a first circuit state, the first and second bus lines are connected via an attenuating resistor having a first resistance value. In a second circuit state, the first and second bus lines are connected via an attenuating resistor having a second resistance value. In a third circuit state, the first and second bus lines are connected via an attenuating resistor having a third resistance value. The first resistance value is lower than the second resistance value. The second resistance value is lower than the third resistance value.

A system for filter enhancement, preferably including one or more analog taps and a controller, and optionally including one or more couplers. The system is preferably configured to integrate with a filter, such as a passband filter or other frequency-based filter. The system can be configured to integrate with an RF communication system, an RF front end, or any other suitable RF circuitry. A method for filter enhancement, preferably including configuring one or more analog taps, and optionally including calibrating a system for filter enhancement and/or receiving temperature information.

A system for filter enhancement, preferably including one or more analog taps and a controller, and optionally including one or more couplers. The system is preferably configured to integrate with a filter, such as a passband filter or other frequency-based filter. The system can be configured to integrate with an RF communication system, an RF front end, or any other suitable RF circuitry. A method for filter enhancement, preferably including configuring one or more analog taps, and optionally including calibrating a system for filter enhancement and/or receiving temperature information.

According to an embodiment, a high frequency integrated circuit includes a signal splitter, an attenuator, a first conductive element, and first to eighth switches. The signal splitter receives a high frequency signal at an input terminal, splits the high frequency signal to two lines, and outputs the signals split into the two lines from a first output terminal and a second output terminal. The attenuator has multiple amounts of attenuation values. In the first conductive element, a first amount of attenuation is set. The high frequency integrated circuit outputs a plurality of output signals having different gain values from the first high frequency output terminal and the second high frequency output terminal, respectively.

A transmission-end impedance matching circuit operates according to a signal of an overvoltage signal source and includes a first level shifter, a voltage generating circuit, and an impedance matching circuit. The first level shifter generates a first conversion voltage according to a source signal and operates between a first high voltage and a ground voltage. The voltage generating circuit generates a second high voltage according to the first conversion voltage, the first high voltage, and a medium voltage. The impedance matching circuit includes a second level shifter, a transistor, and two resistors. The second level shifter generates a gate voltage according to the second high voltage, a low voltage, and an input signal. The transistor is turned on/off according to the gate voltage and has a withstand voltage lower than the first high voltage. Each of the two resistors is coupled between the transistor and a differential signal transmission end.

A radio frequency (RF) transmission circuit includes an input stage, a current-mode mixer coupled to an output of the input stage, an attenuator coupled to an output of the current-mode mixer, and a matching network coupled to an output of the attenuator. The input stage, current-mode mixer, attenuator, and the matching network are configured in a series stack.

A radio frequency (RF) transmission circuit includes an input stage, a current-mode mixer coupled to an output of the input stage, an attenuator coupled to an output of the current-mode mixer, and a matching network coupled to an output of the attenuator. The input stage, current-mode mixer, attenuator, and the matching network are configured in a series stack.

Differential attenuation circuitry, including: first and second input nodes; first and second output nodes; and an impedance network connected between the first and second input nodes and the first and second output nodes to provide a differential output voltage signal between the first and second output nodes which is attenuated compared to a differential input voltage signal applied between the first and second input nodes, wherein the impedance network includes: a common-mode node; a first impedance network connected between the first input node, the common-mode node and the first output node; and a second impedance network connected between the second input node, the common-mode node and the second output node, and wherein the differential attenuation circuitry further includes: an input-to-input path comprising one or more impedances and one or more switches connected between the first and second input nodes to provide a current path independent of the common-mode node.

Disclosed herein are embodiments of a wide bandwidth attenuator circuit having a tunable gain and tunable input impedance. In some embodiments, the wideband attenuator circuit comprises a serial capacitor shunted to ground by a plurality of circuit slices that are connected in parallel and switchably coupled to the output node of the attenuator. Each circuit slice has a tunable resistor that can be set to a conductive state (“enabled”) or a high impedance state (“disabled”) The number of enabled circuit slices that are connected in parallel may be used to program the attenuator gain and the attenuator impedance.

Digital step attenuator (DSA) and digital phase shifter (DPS) multi-stage circuit architectures that provide for high resolution. Embodiments use a dithering approach to weight bit positions to provide a much finer resolution than the lowest-valued individual stage. Bit position weights for stages are determined so as to enable selection of combinations of n bit positions that provide a desired total attenuation or phase shift range while allowing utilization of the large number of states (2.sup.n) available to produce fractional intermediate steps of attenuation or phase shift. The fractional intermediate steps have a resolution finer than the lowest-valued stage. Bit position weights may be determined using a weighting function, including weightings determined from a linear series, a geometric series, a harmonic series, or alternating variants of such series. In some embodiments, at least one bit position has a fixed value that is not determined by the bit position weighting function.