Dinh Q Nguyen

US Patent:

6960792, Nov 1, 2005

Filed:

Sep 30, 2003

Appl. No.:

10/676531

Inventors:

Dinh Quoc Nguyen - San Jose CA, US

Assignee:

National Semiconductor Corporation - Santa Clara CA

International Classification:

H01L023/62
H01L029/74
H01L031/111
H02H009/00

US Classification:

257173, 257111, 257162, 257168, 257355, 257356, 257357, 257546

Abstract:

A bi-directional silicon controlled rectifier structure provides electrostatic discharge (ESD) protection against both positive and negative voltage spikes. The structure utilizes a pair of wells, n+ and p+ regions formed in both wells, a first ring formed around the junction between the first well and the semiconductor material, and a second ring formed around the junction between the second well and the semiconductor material.

US Patent:

7646244, Jan 12, 2010

Filed:

Jul 24, 2008

Appl. No.:

12/179458

Inventors:

Chang Chia Hsiao - San Jose CA, US
Dinh Nguyen - San Jose CA, US

Assignee:

National Semiconductor Corporation - Santa Clara CA

International Classification:

H03F 3/26

US Classification:

330267, 330263

Abstract:

A unity gain buffer is provided. The unity gain buffer includes two complementary pairs of emitter followers and two bias current sources. The top bias current source is arranged to provide a bias current so that, if the input voltage is greater than zero, the bias current provided by the top current source increases at the input voltage increases. The bottom current source is arranged to provide a bias current so that, if the input voltage is less than zero, the bias current provided by the bottom current source decreases as the input voltage decreases.