Abstract: A controller for a phase change switch device, a system including the controller, a phase change switch device, and a corresponding method are provided. The controller includes a control input configured to receive a first control signal indicating a desired state of the phase change switch device and a measurement input configured to receive a measurement signal indicating an actual state of the phase change switch device. A control logic is configured to generate a second control signal based on the first control signal and the measurement signal. The controller further includes a control output configured to output the second control signal to at least one heater of the phase change switch device.

Abstract: A circuit for a switched-mode power supply is described. According to at least one configuration, the circuit comprises a switched-mode converter having a transformer for DC isolation between a primary side and a secondary side of the switched-mode converter, wherein the switched-mode converter is designed to convert an input voltage supplied to the switched-mode converter into an output voltage as stipulated by a switching signal. Arranged on the primary side of the switched-mode converter is a control circuit that is designed to produce the switching signal for the switched-mode converter. The circuit furthermore comprises a DC isolating transmission channel that is used to transmit a modulated feedback signal to the control circuit on the primary side. Arranged on the secondary side of the switched-mode converter is an integrated circuit that has an encoding circuit and a modulator circuit.

Abstract: A semiconductor chip includes an LED driver circuit operably coupled to at least one LED and configured to supply a load current to the at least one LED such that an average load current matches a desired current level defined by a drive signal. A temperature measurement circuit is thermally coupled to the LED driver circuit or the LED(s) or both, and is configured to generate, as drive signal, a temperature dependent signal in such a manner that the drive signal is approximately at a higher constant level for temperatures below a first temperature, is approximately at a lower constant level for temperatures above a second temperature but below a maximum temperature, and continuously drops from the higher constant level to the lower constant level for temperatures rising from the first temperature to the second temperature.

Abstract: A circuit for driving light emitting diodes includes a first semiconductor switch that is responsive to a driver signal and a freewheeling device coupled between a first supply terminal that provides a supply voltage and a second supply terminal that provides a reference potential. An LED and an inductor are coupled in series between a common circuit node of the first semiconductor switch and the freewheeling device and either the first supply terminal or the second supply terminal. A current measurement circuit is coupled to the LED and provides a load current signal that represents a load current passing through the at least one LED. A first feedback circuit includes an on-off controller that receives load current signal and a reference signal, compares the load current signal with the reference signal and generates the driver signal dependent on the comparison.

Abstract: A semiconductor chip includes an LED driver circuit operably coupled to at least one LED and configured to supply a load current to the at least one LED such that an average load current matches a desired current level defined by a drive signal. A temperature measurement circuit is thermally coupled to the LED driver circuit or the LED(s) or both, and is configured to generate, as drive signal, a temperature dependent signal in such a manner that the drive signal is approximately at a higher constant level for temperatures below a first temperature, is approximately at a lower constant level for temperatures above a second temperature but below a maximum temperature, and continuously drops from the higher constant level to the lower constant level for temperatures rising from the first temperature to the second temperature.

Abstract: A circuit for driving light emitting diodes (LEDs) includes a first semiconductor switch and a freewheeling device coupled between a first supply terminal that provides a supply voltage and a second supply terminal that provides a reference potential. The first semiconductor switch is responsive to a driver signal. An LED and an inductor are coupled in series between a common circuit node of the first semiconductor switch and the freewheeling device and either the first supply terminal or the second supply terminal. A current measurement circuit is coupled to the LED and provides a load current signal which represents a load current passing through the at least one LED. A first feedback circuit includes an on-off controller that receives load current signal and a reference signal.

Abstract: A circuit for driving light emitting diodes includes a first semiconductor switch that is responsive to a driver signal and a freewheeling device coupled between a first supply terminal that provides a supply voltage and a second supply terminal that provides a reference potential. An LED and an inductor are coupled in series between a common circuit node of the first semiconductor switch and the freewheeling device and either the first supply terminal or the second supply terminal. A current measurement circuit is coupled to the LED and provides a load current signal that represents a load current passing through the at least one LED. A first feedback circuit includes an on-off controller that receives load current signal and a reference signal, compares the load current signal with the reference signal and generates the driver signal dependent on the comparison.

Abstract: A circuit for driving light emitting diodes (LEDs) includes a first semiconductor switch and a freewheeling device coupled between a first supply terminal that provides a supply voltage and a second supply terminal that provides a reference potential. The first semiconductor switch is responsive to a driver signal. An LED and an inductor are coupled in series between a common circuit node of the first semiconductor switch and the freewheeling device and either the first supply terminal or the second supply terminal. A current measurement circuit is coupled to the LED and provides a load current signal which represents a load current passing through the at least one LED. A first feedback circuit includes an on-off controller that receives load current signal and a reference signal.

Abstract: According to one or more aspects of the present invention, a receiver arrangement is disclosed that is configured to receive digital television signals. The receiver arrangement has at least one first frequency conversion device with the signal input, a local oscillator input and an output. The at least one first frequency conversion device is designed to convert a signal which is applied to the input side to an intermediate frequency. A first amplifier is also provided and is designed with amplification in order to compensate for the signal level loss in a filter which is connected downstream from the first amplifier. The first amplifier is coupled to the output of the frequency conversion device. An intermediate-frequency amplifier with a variable gain factor is also provided, and is coupled to the first amplifier. At least the at least one first frequency conversion device the first amplifier are formed in a common semiconductor body.

Abstract: A circuit arrangement includes two adjustable amplification devices where the signal output of the first amplification device is connected to the signal input of the second amplification device. The first amplification device has a digital input for controlling its gain and the second amplification device has an input for controlling its gain. The input for gain control in the second amplification device is connected to the input for controlling the gain of the first amplification device via a means such that a change in the gain of the second amplification device in one direction is effected by a change in gain, brought about by means of the control, in the first amplification device in the opposite direction such that the total gain remains essentially the same.

Abstract: A transmitting and receiving unit includes a receiving branch and a transmitting branch that are in each case constructed for conducting complex signals, with a control device that drives a switch by which either a phase-locked loop is switched through to frequency converters provided at the transmitting and receiving end, for providing a common carrier frequency, or in each case an independently operating PLL is provided for the transmitting and receiving branch. Such a configuration enables the transmitter, for example, to operate with direct conversion whereas the receiver can operate, for example, on the low IF principle. The invention is suitable for OFDM multi-carrier systems.

Abstract: A circuit arrangement includes two adjustable amplification devices where the signal output of the first amplification device is connected to the signal input of the second amplification device. The first amplification device has a digital input for controlling its gain and the second amplification device has an input for controlling its gain. The input for gain control in the second amplification device is connected to the input for controlling the gain of the first amplification device via a means such that a change in the gain of the second amplification device in one direction is effected by a change in gain, brought about by means of the control, in the first amplification device in the opposite direction such that the total gain remains essentially the same.

Abstract: According to one or more aspects of the present invention, a receiver arrangement is disclosed that is configured to receive digital television signals. The receiver arrangement has at least one first frequency conversion device with the signal input, a local oscillator input and an output. The at least one first frequency conversion device is designed to convert a signal which is applied to the input side to an intermediate frequency. A first amplifier is also provided and is designed with amplification in order to compensate for the signal level loss in a filter which is connected downstream from the first amplifier. The first amplifier is coupled to the output of the frequency conversion devices. An intermediate-frequency amplifier with a variable gain factor is also provided, and is coupled to the first amplifier. At least the at least one first frequency conversion device and the first amplifier are formed in a common semiconductor body.

Abstract: Conventional circuit configurations for range changeover between different bands (UHF, VHF) in television receivers utilize MOS tetrodes whose operating point adjustment is unproblematic. The MOS tetrodes of the inventive circuit configuration comprise a constant potential at their source electrode regardless of the band that is selected. Besides the savings in terms of components, the invention simplifies the dimensioning of the circuit configuration. The invention can be used in all high-frequency receivers having a plurality of frequency ranges between which a changeover is performed.

Abstract: A transmitting and receiving unit includes a receiving branch and a transmitting branch that are in each case constructed for conducting complex signals, with a control device that drives a switch by which either a phase-locked loop is switched through to frequency converters provided at the transmitting and receiving end, for providing a common carrier frequency, or in each case an independently operating PLL is provided for the transmitting and receiving branch. Such a configuration enables the transmitter, for example, to operate with direct conversion whereas the receiver can operate, for example, on the low IF principle. The invention is suitable for OFDM multi-carrier systems.

Abstract: A phase locked loop system for tuning the reception frequency of a receiver for digitally modulated received signals and analog-modulated received signals has at least one voltage controlled oscillator for producing an oscillator signal for a reception frequency tuning. A first frequency divider is provided for dividing the frequency of the oscillator signal to a nominal comparison frequency as a function of a receiving channel selection signal. A second frequency divider is provided for dividing a reference frequency as a function of a reception mode switching signal. A phase comparison circuit is provided for comparing the signals supplied by the frequency dividers in order to produce a tuning voltage for the voltage controlled oscillator wherein the gain of the phase comparison circuit is adjustable in order to optimize the phase noise.

Abstract: A phase locked loop system for tuning the reception frequency of a receiver for digitally modulated received signals and analog-modulated received signals has at least one voltage controlled oscillator for producing an oscillator signal for a reception frequency tuning. A first frequency divider is provided for dividing the frequency of the oscillator signal to a nominal comparison frequency as a function of a receiving channel selection signal. A second frequency divider is provided for dividing a reference frequency as a function of a reception mode switching signal. A phase comparison circuit is provided for comparing the signals supplied by the frequency dividers in order to produce a tuning voltage for the voltage controlled oscillator wherein the gain of the phase comparison circuit is adjustable in order to optimize the phase noise.