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:
Sep. 28, 1999
Filed:
Aug. 03, 1995
Enrico Ravanelli, Milan, IT;
Lucia Zullino, Milan, IT;
STMicroelectronics, S.r.l., Agrate Brianza, IT;
Abstract
The device has an SCR structure in a P surface zone of a silicon die. A P+ anode region for connection to an I/O terminal to be protected is formed in an N region, as well as an N+ contact region; an N+ cathode region is formed in another N region for connection to the earth of the integrated circuit. The striking potential of the SCR, that is, the intervention potential of the protection device, is determined by the reverse breakdown of the junction between the first N region and the P-body surface zone. This potential is influenced by an electrode which is disposed over the junction and is connected to the cathode constituting the gate of a cut-off N-channel MOS transistor. The concentrations are selected in a manner such that the P-channel MOS transistor defined by the P region, by the portion of the first region over which the electrode is disposed, and by the P-body, has a conduction threshold greater than the striking potential. The device can be integrated in a very small area and is very efficient in terms of both energy and response speed.