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:
May. 25, 1999
Filed:
Sep. 07, 1994
Amitava Chatterjee, Plano, TX (US);
Charvaka Duvvury, Plano, TX (US);
Ping Yang, Richardson, TX (US);
Ekanayake Ajith Amerasekera, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A protection device comprising a gate-coupled silicon-controlled rectifier (SCR) (100), SCR (100) comprises an anode (105) formed in n-well (104) and connected to a pad (128) and a cathode (111) connected to ground. A gate-coupled NMOS transistor (120) has a gate (116) connected through a resistive element (118) to ground. A n+ region (112) forms both the cathode (111) and a source of the NMOS transistor (120). N-well (104) forms the drain. Stress voltage is coupled from pad (128) to gate electrode (116) causing NMOS transistor (120) to conduct. This, in turn, triggers SCR (100) which dissipates the stress current at the pad (128). The coupled voltage at gate electrode (116) dissipates within a designed time constant through resistive element (118).