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:
Sep. 19, 1989
Filed:
Dec. 07, 1987
Timothy M Lindenfelser, Eagan, MN (US);
VTC Incorporated, Bloomington, MN (US);
Abstract
A skew compensated RS422 buffer includes a skew compensation circuit and an output driver. The output driver is connected to receive a complementary pair of compensated drive signals, and provides complementary buffer output signals in response thereto. Due to asymmetric switching characteristics, buffer output signals in response to falling edge drive signals are delayed by an inherent skew period with respect to buffer output signals in response to rising edge drive signals. The skew compensation circuit includes a NOR gate and an AND gate, both of which have a first input terminal connected to receive buffer input signals. The buffer input signals are also applied to second input terminals of both the NOR gate and AND gate through delay gates which delay signal propagation by delay periods substantially equal to the inherent skew period of the output driver. A complementary pair of compensated drive signals are provided at output terminals of the NOR and AND gates, thereby compensating for the asymmetric switching characteristics of the output driver means.