Control circuit and method for piezoelectric transformer
August 5, 2019. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesUltrasonic oscillation circuit Power converter with a piezoelectric ceramic transformer Discharge tube driving device and piezoelectric transformer therefor Inverter power source apparatus using a piezoelectric transformer Drive circuit for driving a piezoelectric transformer capable of decreasing heat developed from electronic parts composing an inverter circuit Piezoelectric transformer drive circuit Piezoelectric transformer with monitor electrodes for sensing unbalanced vibration of the transformer Patent #: 5962953 InventorsAssigneeApplicationNo. 355844 filed on 08/05/1999US Classes:310/316.01, Input circuit for simultaneous electrical and mechanical output from piezoelectric element310/317, Input circuit for mechanical output from piezoelectric element310/319Electrical output circuitExaminersPrimary: Budd, Mark O.Attorney, Agent or FirmInternational ClassH01L 041/08Foreign Application Priority Data1997-02-06 JPAbstractWhen an input voltage rises, (the amplitude of) a sine-wave voltage for driving a piezoelectric transformer (1) increases, so that a detection voltage (Vti) rectified by a rectifying circuit (9) also increases. An output voltage from an error amplifier (10) for comparing the detection voltage (Vti) with a reference voltage (Vref2) rises. If the output voltage from the error amplifier (10) rises, a voltage-controlled oscillation circuit (11) decreases the duty ratio of an oscillation signal to be output. In a driving circuit (7), as the duty ratio of the oscillation signal decreases, the amplitude of a fundamental wave contained in a rectangular wave to be output decreases to be a small driving voltage to the piezoelectric transformer (1).Other References
Field of SearchInput circuit for simultaneous electrical and mechanical output from piezoelectric elementCeramic composition (e.g., barium titanate) More than one poling direction (e.g., Rosen transformer) More than two PERIODIC SWITCH IN THE SUPPLY CIRCUIT Piezoelectric ignition systems With transistor control means in the line circuit Double ended (i.e., push-pull) type | |
