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:
Nov. 24, 1998
Filed:
Jun. 13, 1996
Alessandro Brigati, Aix en Provence, FR;
Nicolas Demange, Lessy, FR;
Maxence Aulas, St Haon le Vieux, FR;
Marc Guedj, Pont Saint Esprit, FR;
SGS-Thomson Microelectronics S.A., Saint Genis, FR;
Abstract
Disclosed is a charge pump type of negative voltage generator circuit, constructed on a P type substrate and supplying a negative voltage at one output by the pumping of negative charges in n series-connected pumping cells, n being an integer, these pumping cells including P type transistors whose wells are connected to a node to be positively biased. This circuit includes a switching circuit for selectively supplying, at the node, a voltage for biasing of the wells that is greater than or equal to the potential present at the output so long as this potential is greater than a positive reference voltage, and provides a voltage of fixed value for biasing of the wells when the potential present at the output is smaller than the reference voltage. Thus, the appearance of latchup phenomena in the transistors of the pumping cells is prevented.