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. 11, 1994
Filed:
May. 16, 1991
Kiyoshi Yamamoto, Toyohashi, JP;
Yoshihisa Sato, Kota, JP;
Satoshi Suzuki, Nagoya, JP;
Masayuki Kobayashi, Anjo, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A transmitting circuit is provided which includes a control circuit for transmitting and receiving a communication signal. Transmit information is modulated into a trapezoidal wave signal using a waveform shaping circuit. A communication signal is first generated on the basis of the trapezoidal wave signal and transmitted to a first transmission line. From this communication signal, a second communication signal is generated having an inverted polarity waveform shape relative to the first communication signal. This inverted polarity triangular wave signal is, in turn, output from a second transmission line BUS-. In addition, a receiving circuit is provided for receiving like signals from other communication devices which share the first and second transmission lines BUS+ and BUS-. The receiving circuit includes a comparator circuit for demodulating received signals on the transmission lines to generate square wave equivalent signals which a processing unit can logically interpret. Because communication signals are transmitted (received) and derived in the described manner, they are not subject to adverse effects, such as can result from fluctuation of GND potential levels and power supply differences amongst remote communication systems. Furthermore, because an inverted triangular waveform is generated in addition to, and on the basis of, a regular, modulated triangular wave signal, phase shift problems are avoided and radiation of harmonics noise is favorably reduced even at intermediate, or higher, transmission rates.