Abstract: A current-controlled resistor comprises a first input terminal configured to receive an input signal and a second input terminal configured to receive a current control signal. The resistor comprises a first stage configured to receive the current control signal; the first stage includes first and second PN diodes having first terminals of a first type and second terminals of a second type. The first terminals of the first and second PN diodes are coupled each other and a second terminal of the first PN diode is coupled to the first input terminal. The resistor comprises a second stage configured to receive the current control signal; the second stage includes a third PN diode having first and second terminals of the first and second types, the second terminal of the third PN diode being coupled to the second terminal of the second PN diode.

Abstract: A harmonic rejection mixer includes a differential in-phase signal path and a differential quadrature signal path, a shared differential transconductor for generating a shared transconductor output signal from a mixer input signal, a first selective mixing circuit disposed in the differential quadrature signal path and coupled to the shared differential transconductor, and a second selective mixing circuit disposed in the differential in-phase signal path and coupled to the shared differential transconductor, the first selective mixing circuit is controlled by a first selective control signal and the second selective mixing circuit is controlled by a second selective control signal to selectively supply the shared transconductor output signal to the differential quadrature signal path and the differential in-phase signal path, respectively.

Abstract: A harmonic rejection mixer for carrying out a frequency translation of a mixer input signal having a mixer input frequency, the mixer including an up-conversion mixer for generating an intermediate signal by multiplying the mixer input signal with a first local oscillation signal having a first local oscillation frequency, and a down-conversion mixer for generating a mixer output signal by multiplying the intermediate signal with a second local oscillation signal having a second local oscillation frequency. The first local oscillation frequency and the second local oscillation frequency are greater than the mixer input frequency. The first local oscillation signal is an l-time oversampled sine wave and the second local oscillation signal is an m-time oversampled sine wave.

Abstract: An image frequency rejection mixer has a first differential transconductor that receives a differential mixer input signal, a second differential transconductor that receives the differential mixer input signal and cross-coupled to the first differential transconductor, a first mixing circuit that generates a first differential mixing circuit output signal by mixing a first differential information signal with a first local oscillation signal, a second mixing circuit that generates a second differential mixing circuit output signal by mixing a second differential information signal with a second local oscillation signal, with the first local oscillation signal and the second local oscillation signal being in quadrature, and an image rejection circuit that generates a differential mixer output signal from the first and second differential mixing circuit output signals.

Abstract: A driving circuit comprises a first and a second switching circuit coupled in parallel to a node which is adapted to be coupled to a load, a first and a second detecting circuit, and a synchronizing circuit having an input coupled to the first and second detecting circuits and having an output coupled to the first and second switching circuits. The first detecting circuit detects a current associated with the first switching circuit and the second detecting circuit detects a current associated with the second switching circuit. The synchronizing circuit operates the first and second switching circuits to switch synchronously to a conducting state, and operates the first and second switching circuits to switch synchronously to a non-conducting state in the event that one of the first and second detecting circuits detects a current equal to or higher than a threshold value.

Abstract: A low noise, highly linear transconductor circuit, which may be applied, e.g., in communication systems, includes a first input node for receiving a first input signal of the transconductor circuit and a second input node for receiving a second input signal of the transconductor circuit, and at least a first amplifier, a second amplifier, and a first, second and third resistor. Each of the first and second amplifiers includes an input stage with a combination of at least a transistor of the MOS type and a transistor of the bipolar type, and an output stage for providing a respective output signal of the transconductor circuit and having at least a transistor of the bipolar type. The circuit achieves reduced noise due to output current reuse in the input stage of the amplifiers and cross coupling of bias resistors to result in a highly linear transconductor circuit having very low noise.

Abstract: A frequency synthesizer circuit that reduces undesired spurious sidebands while maintaining phase noise performance having a phase locked loop circuit comprising at least a phase detector, a controlled oscillator, a frequency divider coupled to the controlled oscillator for adjusting a frequency division of the frequency divider in response to a received control signal generated from a divisor value, a dithering circuit for providing a dither signal, and a sigma-delta modulator comprising an input for receiving a multi-bit input signal indicative of at least part of the divisor value. The input of the sigma-delta modulator is coupled with the dithering circuit for receiving the dither signal as a most significant bit of the multi-bit input signal.

Abstract: A transconductor circuit, particularly according to the multi-tanh principle, having a first input node and a second input node, a first differential amplifier coupled to the first and second input nodes, and having a first offset voltage, and a second differential amplifier coupled to the first and second input nodes, and having a second offset voltage different from the first offset voltage. A first resistance circuit is coupled between the first differential amplifier and at least one current source, and a second resistance circuit is coupled between the second differential amplifier and the at least one current source. Varying of the current sources enables control of the transconductance without degrading linearity.

Abstract: An integrated circuit, comprises a wakeup terminal; a supply voltage terminal configured to receive a supply voltage; and a power control circuit. The power circuit comprises an enable circuit coupled to the wakeup terminal and configured to generate a voltage monitoring enable signal as a response to a wakeup signal received at the wakeup terminal, and a voltage monitoring circuit for generating a supply voltage level indication signal. The voltage monitoring circuit is coupled to the supply voltage terminal and comprises an operation switch controlled by the voltage monitoring enable signal. The voltage monitoring circuit is configured to determine if the supply voltage is above a threshold voltage and set the supply voltage level indication signal accordingly. The integrated circuit further comprises processing circuitry, with the supply voltage level indication signal controlling the switching between a normal operation state and a standby state of the processing circuitry.

Abstract: An electrochrome element driver supplies electrical power to an electrochrome element and includes an amplifying circuit, a variable resistor element, and a capacitor. The amplifying circuit has a control input for controlling a supply current flow to the electrochrome element, a feedback input, and an output. The variable resistor element has a first resistor terminal, a second resistor terminal coupled to the feedback input and a resistor control terminal for controlling a resistance of the variable resistor element. The resistor control terminal is coupled to the amplifying circuit output, the first resistor terminal is coupleable to a power source, and the second resistor terminal is coupleable to the electrochrome element such that a supply current path to the electrochrome element through the variable resistor element is formed. The capacitor is coupled to the resistor control terminal for effecting a stable behavior of the supply current flow to the electrochrome element.

Abstract: An electrochrome element driver supplies electrical power to an electrochrome element and includes an amplifying circuit, a variable resistor element, and a capacitor. The amplifying circuit has a control input for controlling a supply current flow to the electrochrome element, a feedback input, and an output. The variable resistor element has a first resistor terminal, a second resistor terminal coupled to the feedback input and a resistor control terminal for controlling a resistance of the variable resistor element. The resistor control terminal is coupled to the amplifying circuit output, the first resistor terminal is coupleable to a power source, and the second resistor terminal is coupleable to the electrochrome element such that a supply current path to the electrochrome element through the variable resistor element is formed. The capacitor is coupled to the resistor control terminal for effecting a stable behavior of the supply current flow to the electrochrome element.

Abstract: A first switching circuit has an input for receiving a first input signal, and a second switching circuit has an input for receiving a second input signal. A node is connected to receive outputs from both the first and second switching circuits. A filter receives an unfiltered signal from the node to generate an output signal. A circuit is provided to alternately actuate the first and second switching circuits during a transition time period so as to smoothly transition the output of the filter between the first and second input signals. At least one of the first and second input signals is a time-varying analog signal. The smooth transition between the first and second input signals has a shape determined by pulse width and frequency characteristics of pulses output by the circuit to alternately actuate the first and second switching circuits. The shape may include a linear ramp, an S-shaped curve, a parabolic curve and a hyperbolic curve.

Abstract: A circuit is provided for controlling a battery-charger device with a closed-loop architecture. The circuit includes sensing means for sensing an operative quantity of the device, control means, and driving means. The control means alternately controls the sensing means to track the operative quantity during a tracking phase and to hold the operative quantity during a holding phase. The driving means provides a regulation signal that regulates the operative quantity based on a comparison between the operative quantity sensed by the sensing means and a reference value. The control means causes the driving means to hold the regulation signal during at least part of each of the holding phases. Also provided is a method of controlling a battery-charger device with a closed-loop architecture.

Abstract: A vehicle navigation system may include an antenna, e.g. a GPS antenna, an output for providing guide advice to the vehicle driver and including a display, a memory encompassing a navigation database with electronic maps stored within, and an electronic controller. The system is capable of detecting the global position of the vehicle on the basis of the electromagnetic waves received by the antenna, associating the global position to the exact road position of the vehicle by comparison with the electronic maps and providing pictorial guide advice to the vehicle driver according to the road position via the display. The system may include a digital camera installed on the vehicle and able to record digital pictures of the outside and to provide the digital pictures to the electronic controller. The pictures are displayed via the display, and pictorial guide advice, e.g. directional arrows, are overprinted to the displayed pictures.