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:
Jul. 19, 2005
Filed:
Oct. 31, 2003
Chen-shang Lai, Taichung, TW;
Meng-huang Liu, Hsin-Chu, TW;
Shin Su, Taipei, TW;
Tao-cheng LU, Kaohsiung, TW;
Chen-Shang Lai, Taichung, TW;
Meng-Huang Liu, Hsin-Chu, TW;
Shin Su, Taipei, TW;
Tao-Cheng Lu, Kaohsiung, TW;
Abstract
The present invention provides a PMSCR (bridging modified lateral modified silicon controlled rectifier having first conductivity type) with a guard ring controlled circuit. The present invention utilizes controlled circuit such as switch to control functionally of guard ring of PMSCR. In normal operation, the switch is of low impedance such that the guard ring is short to anode and collects electrons to enhance the power-zapping immunity. Furthermore, during the ESD (electrostatic discharge) event, the switch is of high impedance such that the guard ring is non-functional. Thus, the PMSCR with guard ring control circuit can enhance both the ESD performance and the power-zapping immunity in the application of the HV (high voltage) pad.