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:
Dec. 12, 1995
Filed:
Oct. 07, 1994
Applicant:
Inventors:
Richard B Merrill, Daly City, CA (US);
Whu-ming Young, Palo Alto, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
G05F / ; G05F / ;
U.S. Cl.
CPC ...
327536 ; 327537 ; 327544 ;
Abstract
A cascaded charge pump includes multiple stages each providing a (nominal) 3 volt increment. Thus a charge pump having an 18 volt range is provided using a CMOS process which normally then allows integration on a single integrated circuit chip of a complex digital logic function such as a UART (universal asynchronous receiver and transmitter) with a high voltage function such as an RS-232 interface, including integrated capacitors for the RS-232 interface charge pump.