Abstract:
A Single Input Dual Output converter includes a first switch coupling an input to a first inductor terminal, a second switch coupling a second inductor terminal to ground, a third switch coupling the second inductor terminal to a positive output, and a fourth switch coupling the first inductor terminal to a negative output. During time-shared control, the negative and positive outputs are independently served by conversion cycles. Each conversion cycle includes: a positive phase with a positive charge phase (closing only the first and second switches), followed by an additional phase (closing only the first and third switches for a given time duration), and followed by a positive discharge phase (closing only the third and fourth switches). Each conversion cycle further includes a negative phase with a negative charge phase (closing only the first and second switches) followed by a negative discharge phase (closing only the second and fourth switches).
Abstract:
Charge pump stages are coupled between flying capacitor pairs and arranged in a cascaded between a bottom voltage line and an output voltage line. Gain stages apply pump phase signals having a certain amplitude to the charge pump stages via the flying capacitors. A feedback signal path from the output voltage line to the bottom voltage line applies a feedback control signal to the bottom voltage line. Power supply for the gain stages is provided by a voltage of the feedback control signal in order to control the amplitude of the pump phase signals. An asynchronous logic circuit generates the switching drive signals for the gain stages with a certain switching frequency which is a function of a logic supply voltage derived from the voltage of the feedback control signal.
Abstract:
A control circuit for controlling switching operation of a switching stage of a converter includes a phase detector circuit that generates a pulse-width modulated (PWM) signal in response to a phase comparison of two clock signals. A first clock signal has a frequency determined as a function of a first feedback signal proportional to converter output voltage. A first transconductance amplifier generates a first current indicative of a difference between a reference voltage and the first feedback signal, and a second transconductance amplifier generates a second current indicative of a difference between the reference voltage and a second feedback signal proportional to a derivative of the converter output voltage. A delay line introduces a delay in the first clock signal that is dependent on the first and second currents as well as a compensation current dependent on a selected operational mode of the converter.
Abstract:
A switching amplifier, such as a Class D amplifier, includes a current sensing circuit. The current sensing circuit is formed by replica loop circuits that are selectively coupled to corresponding output inverter stages of the switching amplifier. The replica loop circuits operated to produce respective replica currents of the output currents generated by the output inverter stages. A sensing circuitry is coupled to receive the replica currents from the replica loop circuits and operates to produce an output sensing signal as a function of the respective replica currents.
Abstract:
A circuit includes an input transistor pair with first and second input transistors, the first input transistor having a control terminal configured to receive an input signal and a cascode transistor pair including a first and second cascode transistors having a common control node. A bias circuit has a bias input configured to receive the input signal and a first bias output coupled to the common node of the first and second cascode transistors. The bias circuit includes a signal tracking circuit operating to generate the first bias output to track the input signal. A pair of load transistors are coupled to the input transistor pair and biased by a second bias output of the bias circuit.
Abstract:
An energy harvesting interface receives an electrical signal from an inductive transducer and outputs a supply signal. An input branch includes a first switch and a second switch connected in series between a first input terminal and an output terminal, and further a third switch and a fourth switch connected in series between a second input terminal and the output terminal. A first electrical-signal-detecting device coupled across the second switch detects a first threshold value of an electric storage current in the inductor of the transducer. A second electrical-signal-detecting device coupled across the fourth switch detects whether the electric supply current that flows through the fourth switch reaches a second threshold value lower than the first threshold value.
Abstract:
A converter includes an inductor configured to receive an input signal and output configured to supply an electrical load with an output signal. The converter operates to charge the inductor until a maximum pre-set current value is reached during a first operating condition in which the electrical load is not supplied. Next, the converter actively supplies the electrical load by partially discharging the inductor during a first time interval of a second operating condition. Then, the converter passively supplies the electrical load by the residual charge of the inductor during a second time interval, subsequent to the first time interval, of the second operating condition, by discharging the inductor completely.
Abstract:
An electrical-energy harvesting system envisages a transducer for converting energy from an environmental energy source into a transduced signal, an electrical energy harvesting interface for receiving the transduced signal and for supplying a harvesting signal, and an energy storage element coupled to the electrical energy harvesting interface for receiving the harvesting signal. The electrical-energy harvesting system also includes a voltage converter connected to the electrical energy harvesting interface for generating a regulated voltage. The harvesting interface samples an open-circuit voltage value of the transduced signal, generates an optimized voltage value starting from the open-circuit voltage value, and generates an upper threshold voltage and a lower threshold voltage on the basis of the optimized voltage value. The harvesting interface controls the voltage converter in switching mode so that the harvesting signal has a value between the upper and lower threshold voltages in at least one operating condition.
Abstract:
A biasing circuit for an acoustic transducer is provided with: a voltage-booster stage, which supplies, on a biasing terminal, a boosted voltage for biasing a first terminal of the acoustic transducer; and filtering elements, set between the biasing terminal and the acoustic transducer, for filtering disturbances on the boosted voltage. The biasing circuit is further provided with switches, which can be actuated so as to connect the first terminal to the biasing terminal of the voltage-booster stage, directly during a start-up step of the biasing circuit, and through the filtering elements at the end of the start-up step.
Abstract:
An energy harvesting circuit receives an input voltage from a transducer and uses a single inductor operating in a DC-DC converter charging mode to generate charging current at a first output coupled to an energy storage device where a supply voltage is stored. The energy harvesting circuit further receives the supply voltage from the energy storage device and uses the same single inductor operating in a DC-DC converter regulating mode to generate load current at a second output where a regulated load voltage is provided. The energy harvesting circuit switches between the charging mode and the regulating mode in accordance with a discontinuous mode (DCM) control process.