Abstract: A multilayer piezoelectric transformer is provided using the longitudinal vibration modes for step-up voltage conversion applications. An input portion polarized to deform in a longitudinal plane is bonded to an output portion. The deformation of the input portion is mechanically coupled to the output portion, which deforms in the same longitudinal direction relative to the input portion. The output portion is polarized in the thickness direction relative its electrodes, and piezoelectrically generates a stepped-up output voltage.

Abstract: An inverter circuit is provided using a voltage converter having multiple layers of piezoelectric ceramic. More specifically, the present invention provides an inverter circuit for a Cold Cathode Fluorescent Lamp (CCFL) incorporating a multilayer piezoelectric transformer that uses the longitudinal resonant vibration mode for step-up voltage conversion. The transformer is driven by a FET half-bridge connected to an oscillator through dual current buffers, one current buffer being driven through and a level shifter and charge pump.

Abstract: A circuit including a transformer, preferably a laminated piezoelectric transducer, in combination with a positive feedback amplifier circuit, capable of serving: 1) to produce either an audible or ultrasonic signal; or 2) as an energy source capable of driving an auxiliary high voltage device with an initial and continuing low voltage source such as a battery.

Abstract: A thickness mode piezoelectric transformer is provided that has masses attached to opposing faces of the transformer. The end-masses increase the thickness of the transformer and decrease its resonant frequency. The end-masses increase the magnitude of resonant vibrations in the output layer(s) as well as the mechanical Q of the device to provide a low profile piezoelectric transformer with high power density. The preferably metal end-masses also act as high voltage output electrodes as well as heat sinks.

Abstract: A laminated multi-layer piezoelectric transformer comprising two elements joined together with a conductive adhesive and having a bead of the conductive adhesive at the point of junction of the two elements on the exterior surface of the laminated multi-layer piezoelectric transformer and a mounting device for use therewith and comprising a conductive base having a first contact, and curvaceous arms extending at generally at right angles from the conductive base about said laminated multi-layer piezoelectric transformer, a portion of said arms contacting said bead and preferably designed to engage the distal ends of the arms of an insulating cap mounted on the opposing side of the laminated multi-layer piezoelectric transformer said cap having a second contact therein. This combination configured for mounting on a circuit board is also described.

Abstract: A contact device for securely and reliably attaching electrical leads to a laminated multi-layer piezoelectric transformer and comprising a pair of conductive lead attachment plates, disposed on opposite sides of the laminated multi-layer piezoelectric transformer, each having first and second surfaces, the first surface having at least one leg extending therefrom to contact the laminated multi-layer piezoelectric transformer at a node and the second surface being sufficient to permit secure and durable attachment of electrical leads thereto. A variety of geometric configurations of the contact device of the present invention suitable or adaptable to a variety of laminated multi-layer piezoelectric transformer geometries are also described. Such a device, useful for the attachment of a laminated multi-layer piezoelectric transformer to a circuit board, is also described.

Abstract: Fluorescent lamp excitation circuits are provided which use a resonating piezoelectric transformer along with complementary circuit components, to efficiently convert a DC first voltage to a transformer-output AC second voltage. In the preferred embodiment of the invention, A High Displacement Piezoelectric (HDP) transformer achieves sufficiently high voltage output to "cold fire" a gas discharge lamp. The disclosed circuit may be modified using conventional electrical sub-circuitry to pre-heat the cathodes of the lamp.

Abstract: Circuits for use in ignition systems are disclosed which use a resonating piezoelectric transformer along with complementary circuit components, to efficiently convert a DC first voltage to a transformer-output AC second voltage. In the preferred embodiment of the invention, a High Displacement Piezoelectric (HDP) transformer converts a DC voltage into an AC voltage which is rectified into a DC signal of sufficiently high voltage to create a spark across the spark gap of a spark plug. The transformer circuit may be a "self resonating" circuit which relies on an initial pulse from turning on the DC power supply to cause the transformer to begin resonating. In a modified circuit the circuit is not "self resonating" and instead has a phase shift oscillator sub-circuit that provides small pulse signals to start the transformer resonating when the circuit is initially turned on.

Abstract: DC-AC voltage transformation circuits are provided which use a resonating piezoelectric transformer along with complementary circuit components, to efficiently convert a DC first voltage to a transformer-output AC second voltage. In the preferred embodiment of the invention, A High Displacement Piezoelectric (HDP) transformer achieves sufficiently high voltage output to "cold fire" a gas discharge lamp. The disclosed circuit may be modified using conventional electrical sub-circuitry to pre-heat the cathodes of the lamp. The transformer circuit may be a "self resonating" circuit which relies on an initial pulse from turning on the DC power supply to cause the transformer to begin resonating. In a modified voltage converter circuit, the circuit is not "self resonating" and instead has a phase shift oscillator sub-circuit that provides small pulse signals to start the transformer resonating when the circuit is initially turned on.