Protective element

• US 6,566,995 B2
• Filed: 05/01/2001
• Issued: 05/20/2003
• Est. Priority Date: 05/17/2000
• Status: Expired due to Term

• Current Assignee: Sony Chemicals Corp. (Dexerials Corporation)
• Original Assignee: Sony Chemicals Corp. (Dexerials Corporation)
• Inventors: Furuuchi, Yuji, Kawazu, Masami
• Primary Examiner(s): Vortman; Anatoly
• Application Number:
  US09/845,334
• Publication Number:
  US 20020014945A1
• Time in Patent Office: 749 Days
• Field of Search: 337/153,154,182-185,159,160,290,295,296,404,405,416 219/517
• US Class Current: 337/183
• CPC Class Codes: H01H 2085/466 with remote controlled forced fusing
• CPC Class Codes: H01H 85/463 with printed circuit fuse
• CPC Class Codes: H01L 23/5256 comprising fuses, i.e. connections having their state changed from conductive to non-conductive
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

A protective element contains a heat-generating member and a low melting metal member on a substrate, in which the low melting metal member is molten by the heat generated by the heat-generating member and flows onto electrodes, which causes the low melting metal member to blow out, Formula (1) below is satisfied:

(cross-sectional area of the low melting metal member)/(surface area of the blowout-effective electrode)≦0.15  (1)

Alternatively, Formula (2) below is satisfied:

2.5≦(inter-electrode distance)/(cross-sectional area of the low melting metal member)≦30  (2)

wheren the inter-electrode distance is defined as the distance between two electrodes, among the low melting metal member electrodes onto which the molten low melting metal member flows, which are adjacent to each other with the low melting metal member interposed therebetween.

Claims

1. A protective element comprising a heat-generating member and a low melting metal member on a substrate, in which the low melting metal member is molten by the heat generated by the heat-generating member and flows onto electrodes, whereby the low melting metal member is blown out, said protective element being characterised in that Formula (1) below is satisfied for at least one of the electrodes onto which the molten low melting metal flows:

2. A protective element comprising a heat-generating member and a low melting metal member on a substrate, in which the low melting metal member is molten by the heat generated by the heat-generating member and flows onto electrodes, whereby the low melting metal member is blown out, said protective element being characterised in that Formula (2) below is satisfied: