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:
Nov. 24, 1998
Filed:
May. 03, 1993
Stephen W Bryson, Cupertino, CA (US);
Alan T Kondo, Cupertino, CA (US);
Don N Lee, San Jose, CA (US);
Fairchild Semiconductor Corp., So. Portland, ME (US);
Abstract
A method and apparatus for adjusting charging and discharging currents of a pin driver to optimize slew rates and overshoot for different types of logic circuits. The current charging and discharging circuits include respective transistors that are mirrored to a transistor whose current varies in accordance with VH-VL where VH and VL are programmed reference voltages defining the high and low voltage levels of the output driver pulses. Thus, when VH-VL is relatively large such as for CMOS outputs, slew rates are relatively high. However, when VH-VL is relatively small such as for ECL outputs, slew rates are reduced to prevent excessive overshoot.