The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 30, 2001
Filed:
Dec. 17, 1996
George A. Burnett, Coatesville, IN (US);
Robert L. Leonard, Jr., Indianapolis, IN (US);
Yosemite Investiment Inc., Indianapolis, IN (US);
Abstract
A microcontroller is used to drive a piezoelectric transducer. Certain pins on the microcontroller are indicative of selection signals. The selector can be activated either by a user directly (e.g., by pushing buttons), by an offboard actuator (e.g., another microcontroller), or by any method known in the art for activating switches. In one embodiment, an output pin of the microcontroller acts as output for a high-low oscillator. The oscillation amplitude toggles between 0 and 5 volts in a square wave fashion. The output pin is coupled to the base of a bipolar junction transistor so that the transistor turns on and off as a switch in response to the high-low oscillations. As the transistor turns on and off, supply voltage is routed through a network of logic inverters, after first passing through a current limiting impedance means such as a resistor, to the piezoelectric transducer in a manner designed to provide a voltage swing at the transducer on the order of two times the supply voltage for each oscillation. In another embodiment, instead of using a single pin on the microcontroller to alternately forward and reverse bias a single transistor, the microcontroller actuates predetermined pins that are connected to different RC oscillators. The RC oscillators are then connected to the driving circuit. The circuit includes a voltage regulator connected at an input to the supply voltage and at an output to the power supply pin of the microcontroller.