Driver circuitry for piezoelectric transducers
AssigneeCirrus Logic, Inc.
InventorsJohn Paul Lesso, Toru Ido
Life of this patent
Estimating the term…
Abstract
The present disclosure relates to driver circuitry for driving a piezoelectric transducer. The circuitry comprises: a power supply; a reservoir capacitance; switch network circuitry; and control circuitry. The control circuitry is configured to control operation of the switch network circuitry so as to charge the reservoir capacitance from the power supply and to transfer charge between the reservoir capacitance and the piezoelectric transducer.
Claims22
Circuitry for driving a piezoelectric transducer based on an input signal, the circuitry being configured to receive a supply of power from a power supply, the circuitry comprising:
- a reservoir capacitance;
- switch network circuitry;
- monitoring circuitry configured to monitor a level or magnitude of the input signal and to output a signal indicative of the level or magnitude of the input signal;
- and
- control circuitry configured to control operation of the switch network circuitry so as to charge the reservoir capacitance from the power supply and to transfer charge between the reservoir capacitance and the piezoelectric transducer;
- wherein the control circuitry is further configured to control operation of the switch network circuitry to
- transfer charge from the power supply to the reservoir capacitance based on the signal indicative of the level of the input signal.
Circuitry for driving a piezoelectric transducer based on an input signal, the circuitry being configured to receive a supply of power from a power supply, the circuitry comprising:
- a reservoir capacitance;
- switch network circuitry;
- monitoring circuitry configured to monitor a level or magnitude of the input signal and to output a signal indicative of the level or magnitude of the input signal;
- and
- control circuitry configured to control operation of the switch network circuitry so as to charge the reservoir capacitance from the power supply based on the signal indicative of the input signal.
Circuitry for estimating a level of charge on a piezoelectric transducer, the circuitry comprising:
- an inductor for transferring charge to the piezoelectric transducer from a charge source;
- control circuitry configured to control transfer of charge to the piezoelectric transducer based on an input signal,
- wherein the control circuitry is configured to receive an indication of a current through the inductor and an indication of a voltage across the piezoelectric transducer,
- and wherein the control circuitry is configured to estimate the level of charge on the piezoelectric transducer based on:
- the indication of the voltage across the piezoelectric transducer when a frequency of the input signal is within a first range, and
- the indication of the current through the inductor when the frequency of the input signal is within a second range.
Dependencies are inferred from the claim text.