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:
Mar. 14, 1989
Filed:
May. 15, 1987
Applicant:
Inventors:
Robert Essaff, Fremont, CA (US);
Robert C Dobkin, San Jose, CA (US);
Assignee:
Linear Technology, Inc., Milpitas, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 61 ; 363 63 ;
Abstract
A charge pump circuit is integrated form utilizes a dual emitter transistor switch having low saturation voltage. The low saturation voltage for the transistor is provided by deriving a base bias voltage from the doubled voltage (2V.sub.cc) and a collector voltage from the voltage supply (V.sub.cc). Current-limiting for the transistor is provided by connecting one emitter to the base bias circuitry whereby the second emitter acts as a collector when the transistor saturates, thereby limiting the base drive and causing current-limiting.