Telefonaktiebolaget Lm Ericsson (publ)

Huawei Technologies Co., Limited

Infineon Technologies Ag

Infineon Technologies Wireless Solutions Sweden Ab

Anders Emericks

Henrik Helmer Hellberg

Carl-Henrik Jorgen Malmgren

Christian Grewing

Mattias Israelsson

Anders Jakobsson

Bingxin Li

Ola Pettersson

Hans Oskar Eriksson

Stefan Van Waasen

Håkan Sjödin

Henrik Sandstrom

A method and apparatus for generating a carrier frequency signal is disclosed. The method includes generating a first frequency signal; injecting a modulation signal at a first point of the two-point modulation architecture; generating a second frequency signal from the modulation signal; introducing the second frequency signal by mixing the first frequency signal and the second frequency signal to generate a mixed frequency signal and outputting the carrier frequency signal selected from the mixed frequency signal.

Method and apparatus for generating a carrier frequency signal

A Digital Calibration System for a Phase Locked Loop includes a Tuning Voltage Controller configured to set the tuning voltage to a value; a Phase Difference Quantizer configured to output a phase difference after comparing a phase of the reference signal with a phase of the feedback signal; a Digital Controller configured to receive the phase difference of the PDQ and control a coarse tuning signal such that an average phase difference of the PDQ is 0; and a Frequency Calibration Logic configured to calibrate the feedback signal in response to the output of the DC.

System and method for calibrating output frequency in phase locked loop

A VCO device is described that has pre-compensation. Digitally switchable compensation capacitors are selectively activated to adjust operation of the VCO to mitigate undesirable operational effects. In some example embodiments, the digitally switchable compensation capacitors of the VCO are adjusted to compensate for the effects of activating (from a quiescent state) an output buffer driven by the VCO.

VCO pre-compensation

A method and a device for determining closed loop bandwidth characteristic of a Phase Locked Loop (PLL) () comprising a voltage controlled oscillator (VCO) () controlled by means of a tuning voltage (V) is disclosed. An embodiment of the invention compares the VCO tuning voltage (V) to a low threshold voltage (V) and a high threshold voltage (V), creating an oscillation of the VCO tuning voltage by offsetting the divider value such that the PLL () forces the tuning voltage (V) towards the high threshold voltage (V) when the low threshold voltage (V) is reached, and offsetting the divider value such that said PLL () forces the tuning voltage (V) towards the low threshold voltage (V) when the high threshold voltage (V) is reached, measuring the period of the oscillation between the high and the low threshold voltage of the VCO tuning voltage by counting the number of cycles of a reference clock signal (clk), and comparing the number of reference clock cycles to a reference number of clock cycles to determine the relative loop bandwidth of the PLL ().

Time-domain measurement of PLL bandwidth

A subscriber line interface circuit (') for supplying line current (IL&#x2032;) to a two-wire transmission line connected to a load (RL&#x2032;), comprises a single current amplifier (&#x2032;). That single current amplifier (&#x2032;) is to be connected with its output terminal to one (B&#x2032;) of the wires (A&#x2032;, B&#x2032;) of the transmission line, while the other wire (A&#x2032;) of the transmission line is to be connected to a voltage source (V&#x2032;) that can be provided within the subscriber line interface circuit (&#x2032;) or external thereto.

Subscriber line interface circuit

In a circuit designed to output a varying output voltage, the substrate of the semi-conductor component is connected to a regulator, in particular a switch, connected to a lower potential than the potential of the substrate of the circuit. The circuit can for example be used in a Subscriber Line Interface Circuit (SLIC).

Semiconductor circuit regulator

In a method and a device for controlling the magnitude of the generated ring signal in a the Subscriber Line Interface Circuit (SLIC) the voltage of the A and B lines to the subscriber from the SLIC is compared to a reference voltage. The device is arranged to control the magnitude of the generated ring signal voltage in response to the outcome of the comparison. In particular, the device is arranged to control the ring signal voltage so that the ring signal voltage is reduced if the voltage on the A or B line exceeds the reference voltage. Also, the reference voltage is preferably chosen so that there is no risk for saturation of the final stages. The reference voltage is preferably selected to have a value being related to the value of the negative supply voltage.

Method of generating a ring signal in a subscriber line interface circuit technical field

Line circuits can be supplied with a first voltage or a second voltage of a lower absolute value. At least the second voltage is variable. The line voltages of at least active line circuits are measured, and possible values for the second voltage are prognosticated. It is determined which line circuits can be supplied with the respective possible value, and the power consumption of those line circuits is calculated using each possible value. For the line circuits which cannot be so supplied, the power consumption is calculated using the first voltage. For each possible value prognosticated for the second voltage, the total power consumptions are summed, and the value that gives the lowest total power consumption is selected as the second voltage. The line circuits are then supplied with the first voltage or the selected second voltage.

Method and arrangement for choosing supply voltage

To reduce power losses in a SLIC comprising first and second current amplifiers supplying line current to respective wires of a two-wire transmission line to a load, a line current detector detects line currents below a threshold value. For line currents above the threshold value, the second amplifier is supplied from a first battery with a substantially constant voltage. A voltage regulator is connected with its output terminal to the second amplifier, with its current supply terminal to a second battery of higher absolute voltage than said first battery, and with its input terminal to the detector. In response to line currents below said threshold value, the detector outputs control signals proportional to the detected line currents to control the output terminal of the voltage regulator to supply the second amplifier as well as the load from the second battery.

Arrangement in a subscriber line interface circuit

The present invention relates to a method and a device for diversion of power in an electric circuit (,), e.g. a subscriber circuit with a balanced two-wire transmission, comprising a user (,) with a variable voltage requirement, which is controlled by the supply characteristic of the device and the resistance in the two-wire transmission (A,B,L). The voltage requirement of the user is fed back via a reference signal (U,) to an input of a voltage-regulating circuit (,), which supplies the user with a drive voltage (V,) adapted to the value of the reference signal. The voltage-regulating circuit (,) is fed with a supply voltage (V,) and a regulator voltage (V,) is defined as the difference between the drive voltage (V,) and the supply voltage (V,). Parallel with the voltage-regulating circuit, an external device (,), e.g. a resistance, is connected in order to divert an undesired power generation in the voltage-regulating circuit through the whole or part of the supply current of the user being led to the external resistance and there the whole or part of the power generation is emitted.

System and method for dissipating heat in an electric device

In a subscriber line interface circuit connected to a telephone line having a high potential wire and a low potential wire, an arrangement for generating a signal for determining the line voltage comprises means (,) for alternately charging a capacitor (,), by means of a first DC current, to a first voltage, and discharging the capacitor (,), by means of a second DC current, to a second voltage. Hereby, a sawtooth wave having an amplitude corresponding to the difference between the first and second voltages is produced. This sawtooth wave is converted to a pulse train related to the line voltage, from which the line voltage can be determined.

In a method and an arrangement for controlling the operating mode of a subscriber line interface circuit by mode control signals from a control circuit which is connected to the subscriber line interface circuit, the subscriber line interface circuit includes at least one latch which is interconnected between the control circuit and the subscriber line interface circuit. The latch is adapted to latch the mode control signals received from the control circuit in response to latch enable signals received from the control circuit, and to apply those latched mode control signals to the subscriber line interface circuit to control its operating mode.

Method and an arrangement for controlling the operating mode of a

In a subscriber line interface circuit connected to a two-wire telephone line (A and B lines) for transmitting AC signals, one of the wires (e.g., the A line) is set to a DC voltage lower (i.e., more negative) than a first DC voltage (GND), while the second wire (e.g., the B wire) is set to a DC voltage lower than the DC voltage of the first wire, but higher than a second DC voltage (VREG). A first voltage generator is provided for setting a first threshold voltage (VTHA) between the first DC voltage (GND) and the DC voltage of the first wire. A second voltage generator is provided for setting a second threshold voltage (VTHB) between the second DC voltage (VREG) and the D voltage for the second wire. The first and second threshold voltages are utilized for transmission and reception of AC signals on the respective A and B wires. As long as the instantaneous value (VA) of the signal on the first wire (A) equals the first threshold voltage (VTHA) and/or the instantaneous value (VB) of the signal on the second wire (B) equals the second threshold voltage (VTHB), the subscriber line interface circuit automatically adjusts the signal headroom to the actual amplitude of the AC signals by controlling the voltage difference (VA) between the first DC voltage (GND) and the DC voltage of the first wire (A) and/or the voltage difference (VB) between the DC voltage of the second wire (B) and the second DC voltage (VREG).

Growing community of inventors

Solna, Sweden

Anders Emericks