Abstract: A circuit for generating a voltage waveform at an output node includes a first voltage rail configured to be held at a first voltage, the first voltage rail being connected to the output node via a first voltage rail switch, a second voltage rail configured to be held at a second voltage that is different from the first voltage, the second voltage rail being connected to the output node via a second voltage rail switch, at least one anchor node connected to the output node via an inductor and an anchor node switch, and a control unit configured to switch the circuit between: a first voltage outputting state in which the first voltage rail switch is closed and the second voltage rail switch is open, and a second voltage outputting producing state in which the second voltage rail switch is closed and the first voltage rail switch is open.

Abstract: A circuit for generating a voltage waveform at an output node. The circuit includes a first voltage rail configured to be held at a first voltage, wherein the first voltage rail is connected to the output node via a first voltage rail switch; a second voltage rail configured to be held at a second voltage that is different from the first voltage, wherein the second voltage rail is connected to the output node via a second voltage rail switch; at least one anchor node connected to the output node via an inductor and an anchor node switch; and a control unit configured to switch the circuit between: a first voltage outputting state in which the first voltage rail switch is closed and the second voltage rail switch is open such that the output node is clamped to the first voltage; and a second voltage outputting producing state in which the second voltage rail switch is closed and the first voltage rail switch is open such that the output node is clamped to the second voltage.

Abstract: Control circuitry for stabilizing a DC voltage outputted by a DC power supply against changes in ambient temperature. The control circuitry includes: measurement circuitry configured to output a measurement voltage representative of a DC voltage outputted by a DC power supply; reference circuitry configured to output a reference voltage; and comparison circuitry configured to compare the measurement voltage with the reference voltage and, based on the comparison, output a control signal for controlling the DC voltage outputted by the DC power supply. At least one temperature-sensitive component of the control circuitry is located in an enclosure configured to maintain a substantially constant temperature within the enclosure.

Abstract: Control circuitry for stabilising a DC voltage outputted by a DC power supply against changes in ambient temperature. The control circuitry includes: measurement circuitry configured to output a measurement voltage representative of a DC voltage outputted by a DC power supply; reference circuitry configured to output a reference voltage; and comparison circuitry configured to compare the measurement voltage with the reference voltage and, based on the comparison, output a control signal for controlling the DC voltage outputted by the DC power supply. At least one temperature-sensitive component of the control circuitry is located in an enclosure configured to maintain a substantially constant temperature within the enclosure.

Abstract: A telephone line power strip-off circuit includes a low loss polarity guard sub-circuit, a low loss line seize sub-circuit, a low loss speech transformer sub-circuit and a high efficiency switched mode power supply which has an output voltage less than the input voltage, arranged to recover 80% approximately of the power presented to the terminals of the phone.