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:
Apr. 24, 2001
Filed:
Jun. 15, 1999
Ronald C. Alford, Plantation, FL (US);
Frederick L. Martin, Plantation, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A wideband level shift circuit (,) used with low voltage ECL or CML topologies. includes a sub-Vbe voltage reference (,) whose output voltage is offset some fraction of a diode voltage drop below a supply voltage, where the fraction is held at a constant value as the diode voltage varies with temperature. A comparator circuit (,) is attached to the reference voltage circuit (,) as well as to a current sourcing transistor and differential buffer circuit (,). The comparator circuit (,) maintains the DC potential at the output of a current sourcing transistor so that the common-mode DC level of the output signal from a differential buffer is shifted down by a fraction of a diode drop from the common-mode DC level of a wideband AC input signal. The shift circuit (,) offers the advantages of a fraction of a diode DC voltage drop with little loss of AC signal bandwidth for circuits operating from low supply voltages.