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. 28, 1999
Filed:
Feb. 18, 1997
Kevin S Donnelly, San Francisco, CA (US);
Chanh Tran, San Jose, CA (US);
Michael Ching, Sunnyvale, CA (US);
Bruno Garlepp, Mountain View, CA (US);
Rambus Inc., Mountain View, CA (US);
Abstract
A bus driver circuit having slew rate control. According to one embodiment, the bus driver circuit includes the following elements: a first circuit having an input configured to receive a data signal and an output operative to output a drive signal in response to the data signal; a second circuit coupled in parallel with the first circuit and operative to receive a slew rate control signal; and a slew rate indicator circuit coupled to the second circuit. The slew rate indicator circuit determines the state of the slew rate control signal in response to operating conditions that cause variations in the slew rate of the drive signal such that when the slew rate control signal is asserted, the second circuit is enabled to affect the slew rate of the drive signal. For one embodiment, the slew rate indicator includes a pulse generator circuit and a clocked comparator circuit. The pulse generator circuit is operative to receive a clock signal and generate a pulse in response to a first transition of the clock signal. The clocked comparator is coupled to the pulse generator circuit and operative to receive the pulse. The clocked comparator determines the state of the slew rate control signal by sampling for the pulse in response to a second transition of the clock signal.