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. 05, 1992
Filed:
Mar. 23, 1990
Applicant:
Inventor:
James K Roberge, Lexington, MA (US);
Assignee:
Massachusetts Institute of Technology, Cambridge, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03K / ; H03K / ; H03K / ; H01S / ;
U.S. Cl.
CPC ...
307270 ; 307311 ; 307315 ; 372 38 ;
Abstract
A diode driver circuit has an adjustable, fixed-value current source and a variable offset current source for drawing a bias current through a laser diode. A Darlington pair buffer circuit isolates the diode from the rest of the driver circuit. The output current of the offset current source is controlled by a number of digital-to-analog converters each controlling a different contribution to the total offset current. A diode protector circuit protects the diode when the system is in an inactive state.