Light-emitting device and lighting device provided with the same
A light-emitting device capable of ensuring an electric connection between a light-emitting element and an electrode without generating any problem in practical use, by both connecting methods with a solder and a connector, and a lighting device provided with the light-emitting device are provided. The light-emitting device according to the present invention has a plurality of LED chips, and a soldering electrode land and a connector connecting electrode land electrically connected to the chips, on a ceramic substrate. The soldering electrode land is formed of a first conductive material having a function to prevent diffusion to a solder, and the connector connecting electrode land is formed of a second conductive material having a function to prevent oxidation.
1. A light-emitting device comprising:
a ceramic substrate having a rectangular outer shape in a top view;
a plurality of LED chips positioned around a center of a primary surface of said ceramic substrate;
a resin dam formed on the primary surface of said ceramic substrate and provided so as to surround a mounting area in which said plurality of LED chips are provided;
a first electrode land and a second electrode land which are electrodes to be connected to a power supply and are electrically connected to said plurality of LED chips, said first and second electrode lands being provided outside said resin dam and near corners of the primary surface of the substrate diagonally opposite to each other, each of said first and second electrode lands having a shape defined by first and second sides along the sides of said ceramic substrate defining the corresponding corner, third and fourth sides shorter than and opposing to the first and second sides, respectively, and a fifth side between the third and fourth sides;
a first wire pattern provided on said ceramic substrate including a first leading line, said first leading pattern being located between said first electrode land and said resin dam;
a second wire pattern provided on said ceramic substrate including a second leading line, said second leading pattern being located between said second electrode land and said resin dam; and
a resin layer provided attaching to an inner side of said resin dam and covering said plurality of LED chips, wherein
said plurality of LED chips are electrically connected to said first and second electrode lands via said first and second leading patterns, respectively,
at least one of said first and second sides of said first electrode land is longer in length than a width of said first leading pattern, and
at least one of said first and second sides of said second electrode land is longer in length than a width of said second leading pattern.
2. The light-emitting device of claim 1 , wherein
each of said first and second sides of said first electrode land is longer in length than a width of said first leading pattern, and
each of said first and second sides of said second electrode land is longer in length than a width of said second leading pattern.
3. The light-emitting device of claim 1 , wherein said first and second electrode lands include silver.
4. The light-emitting device of claim 1 , wherein said first and second leading patterns are line pattern.
5. The light-emitting device of claim 1 , wherein said resin dam has a circular ring shape.
6. The light-emitting device of claim 5 , wherein said first wire pattern and second wire pattern have respective arc shapes under said resin dam each constituting a part of a same circular ring.
7. The light-emitting device of claim 1 , wherein said ceramic substrate has a thickness of about 1 mm.
8. The light-emitting device of claim 1 , wherein said ceramic substrate has an elongated shape in top view.
9. The light-emitting device of claim 8 , wherein a shorter side of said ceramic substrate is 20 mm and a longer side of said ceramic substrate is 24 mm.
10. The light-emitting device of claim 1 , wherein each of said first to fifth sides of said first electrode land is provided on the primary surface of said ceramic substrate so as to be away from an edge of said ceramic substrate.
11. The light-emitting device of claim 10 , wherein each of said first to fifth sides of said second electrode land is provided on the primary surface of said ceramic substrate so as to be away from an edge of said ceramic substrate.
12. The light-emitting device of claim 1 , wherein each of said first to fifth sides of said second electrode land is provided on the primary surface of said ceramic substrate so as to be away from an edge of said ceramic substrate.