Xiaopeng Yang

US Patent:

20070045287, Mar 1, 2007

Filed:

Aug 26, 2005

Appl. No.:

11/213201

Inventors:

Xiang-Ming Li - San Diego CA, US
Xiaopeng Yang - San Diego CA, US
Liwu Wang - San Diego CA, US
Daniel Chang - Rancho Santa Fe CA, US

International Classification:

H05B 1/02

US Classification:

219505000

Abstract:

An improved PTC device and method of manufacturing is disclosed. In one embodiment, the device and method incorporates an improved metal-ceramic composite PTC material manufactured by: (a) heating a ceramic material to a sufficiently high temperature to induce the ceramic material's PTC properties; (b) grinding the ceramic PTC material into a powder; (c) mixing the ceramic PTC material powder with a metal material powder so as to produce a metal-ceramic composite material powder; and (d) sintering the composite material powder at a temperature between 600 and 950 C. In alternative embodiments, an improved multi-layer structure and method of manufacturing such a structure is disclosed. In various embodiments, a PTC device made in accordance with the improved multi-layer structure and method of manufacture may or may not incorporate the improved metal-ceramic composite PTC material disclosed herein, but may use conventional ceramic-based PTC materials.