Abstract:
In an embodiment, a method includes: providing a voltage setpoint to a voltage converter; generating an output voltage at a voltage rail with the voltage converter based on the voltage setpoint; when the voltage setpoint is transitioning from a first voltage setpoint to a second voltage setpoint that has a lower magnitude than the first voltage setpoint, providing a first constant current to a first node coupled to a control terminal of an output transistor to turn on the output transistor, where the output transistor includes a source terminal coupled to a first terminal of a first resistor, and where a current path of the output transistor is coupled to the voltage rail; and turning off the output transistor after the output voltage reaches the target output voltage corresponding to the second voltage setpoint.
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 energy-scavenging interface includes first and second switches connected in series between an input and reference, and third and fourth switches connected in series between the input and an output. A control circuit closes the first and second switches and opens the third switch for a first time interval to store charge in a storage element. A scaled copy of a peak value of the charging current is obtained. The control circuit then opens the first switch and closes the third and fourth switches to generate an output signal as long as the value in current of the output signal is higher than the value of said scaled copy of the peak value.
Abstract:
A dual input single output (DISO) regulator, includes a comparator configured to receive a first and second power supply signal and to provide a first compared signal; a first switch configured to couple the first power supply source to an intermediate node, and a second switch configured to couple the second power supply source to the intermediate node; a control logic circuit, coupled to the first comparator, to the first switch, and to the second switch, and configured to receive the compared signal to control the first and the second switch in a first and second operating condition based on the compared signal. The intermediate node being biased by an intermediate power supply signal correlated to the first or second power supply signal. The DISO regulator includes a low-dropout regulator, configured to provide a regulated power supply signal based on the intermediate power supply signal.
Abstract:
A MEMS speaker device including a membrane that forms a first capacitor and a second capacitor, respectively, with a top plate and with a bottom plate. The device includes a driving circuit that operates, during a first operating period, to move the membrane into a first position, in which the membrane is close to the bottom plate, and during a second operating period, to move the membrane into a second position, in which the membrane is close to the top plate. The device includes a testing circuit having a measuring circuit, which generates a first signal, based on a capacitance of one of the first capacitor and the second capacitor and a second signal based on a capacitance of one of the first capacitor and the second capacitor; and a comparator, which compares the first and second signals with at least one first electrical reference quantity.
Abstract:
An energy-scavenging interface receives an input signal from a transducer and supplies an output signal to a load. A switch is connected between the transducer and a reference node, and a diode is connected between the transducer and the load. A control circuit closes the switch for a time interval to permit energy storage in the transducer. A scale copy of a peak value of stored electric current is obtained. The switch is opened when the time interval elapses and the stored energy exceeds a threshold. The stored energy is then released to supply the load through the diode. The switch remains open as long as the value of current in the output signal exceeds the value of the scaled copy of the peak value.
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.