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:
Jun. 22, 1982
Filed:
Jun. 30, 1980
Applicant:
Inventor:
Thomas M Frederiksen, San Jose, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
H01C / ; G05F / ;
U.S. Cl.
CPC ...
323231 ; 357 13 ; 357 35 ; 357 42 ; 357 86 ; 357 23 ;
Abstract
Butted guard band CMOS circuits have a typical breakdown of about 7 volts. It is often desirable to operate circuitry from supplies greater than 7 volts. For example, 9 volts is a commonly used supply value. An isolated zener diode is fabricated into a CMOS integrated circuit so as to develop a voltage drop equal to guard band breakdown. The zener voltage is coupled by way of a diode-connected transistor to the operating circuitry. The diode drop substracts from the zener voltage so that the circuitry is always operated at a voltage below its breakdown.