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:
May. 03, 1994
Filed:
Sep. 29, 1992
Hamed Ghassemi, Austin, TX (US);
Perry H Pelley, III, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A power supply dependent input buffer (20) having a differential amplifier (22), emitter-follower transistors (29 and 32), level shifting resistors (30 and 33), and power supply dependent current sources (31 and 34) receives an ECL input signal referenced to a positive power supply voltage and provides buffered level shifted signals referenced to ground. The current sources (31 and 34) receive a power supply dependent bias voltage that changes in relation to a change in the positive power supply voltage. In turn, the voltage drop across the resistors (30 and 33) changes with respect to the positive power supply voltage such that the buffered level shifted signals are constant with respect to ground. The power supply dependent input buffer (20) is for use at low power supply voltages (such as 3.3 volts), resulting in low power consumption and wider margins on following stages, such as a level converter.