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:
Mar. 12, 1996
Filed:
May. 05, 1994
John Z Wang, Stockton, CA (US);
Timothy S Lee, Santa Cruz, CA (US);
Bairu L Wong, Stockton, CA (US);
FORTIS CO., Stockton, CA (US);
Abstract
A waveform synthesizer includes a data memory, an address manager, an interface and a pulse generator. The data memory has a pulse-width value storage for storing values obtained from sampling a low frequency periodic waveform at a high sampling rate. These values stored in the storage can be scaled in response to a requested magnitude by a scaler within the data memory, thereby generating a look-up table with a series of addresses. The address manager includes an address generator and an address incrementer. The address generator generates address codes for accessing the look-up table through the series of addresses. The address incrementer then adjusts the magnitude of the address increments in response to requested frequency input from the interface. The address increments are proportional to the frequency so that when the requested frequency is high, the address increments are large and more addresses are skipped over between retrieve operations. The pulse generator is provided to convert the retrieved values into pulse trains. The typical application of the waveform synthesizer is to drive an AC motor.