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. 02, 1993
Filed:
Mar. 30, 1990
Norio Takenouchi, Tenri, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
Pulse wave modulation waveform signals of three-phase alternating-current necessary for driving a compressor used in an air-conditioner incorporating an inverter circuit are, for example, generated by preliminarily storing the reference waveform data in a ROM, reading out sequentially, and executing specified data conversion instructions. In a signal generation circuit of the invention, a waveform generation circuit for execution of such data conversion is provided independently of a central processing unit (CPU), and after setting initial data from the CPU, the waveform data are directly read into the waveform generation circuit from the ROM by DMA transfer system to perform data conversion. That is, the CPU is not related with the data conversion, and therefore it is not necessary to create waveform data reading program and data conversion program.