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:
Aug. 03, 2010
Filed:
Aug. 30, 2007
Amit Kumar Rathi, Madhya Pradesh, IN;
Ankit Srivastava, Uttar Pradesh, IN;
Paras Garg, Uttar Pradesh, IN;
Amit Kumar Rathi, Madhya Pradesh, IN;
Ankit Srivastava, Uttar Pradesh, IN;
Paras Garg, Uttar Pradesh, IN;
STMicroelectronics Pvt. Ltd., Uttar Pradesh, IN;
Abstract
An output buffer circuit for improving an output during state transitions of CMOS buffers driving transmission line loads. The circuit generates variable output impedance proportional to the load transmission line impedance. The buffer includes an output stage, such as pull up/pull down drivers for receiving an input signal and generating an output signal. The pull up/pull down drivers are biased by a circuit that generates a control signal and varies its conductivity according to the control signal. The pull up/pull down drivers initially provide a relatively low impedance to reach a desired level during the initial transition period of the output and then slowly varies its impedance in response to the control signal to suppress the ringing effect. The control circuit coupled to the input node, output node and the power supply node to generate a control signal that biases the pull up/pull down driver.