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:
Feb. 01, 2005
Filed:
May. 13, 2002
Brian Donovan, Vancouver, WA (US);
Ray S. Mckaig, Vancouver, WA (US);
Brian Donovan, Vancouver, WA (US);
Ray S. McKaig, Vancouver, WA (US);
Xyron Corporation, Vancouver, WA (US);
Abstract
A method and circuit are provided for converting a digital signal to an analog signal in the form of a pulse width modulated (PWM) pulse (). The PWM pulse is generated during an output cycle of a pulse generator to form a pulsetrain output of pulses at a fixed frequency whose widths are determined by dynamically changing digital input data. The method includes the steps of dividing the digital data signal into most significant bit (MSB) and least significant bit (LSB) portions. A PWM pulse is initiated at the beginning of an output cycle and continues while the MSB portion counts down in a counter (). At the same time, the LSB portion of the digital data signal is converted to a precise phase delay signal which is a subcycle of an oscillator controlling the counter. This phase delay signal is generated after the termination of the MSB count, and halts the high period of the PWM pulse during the output cycle. When the output cycle ends, the process is repeated with the next digital signal.