Patent ID: 7609143

Claim:
A multi-layer type over-current and over-temperature protection structure, comprising: at least two over-current and over-temperature protection elements, wherein each over-current and over-temperature protection element has a top electrode layer, a bottom electrode layer, a positive temperature coefficient material layer disposed between the top electrode layer and the bottom electrode layer, and each over-current and over-temperature protection element has a power input portion, a power output portion, and a plurality of insulative portions for limiting currents in each over-current and over-temperature protection element to only flow from the power input portion to the power output portion through the positive temperature coefficient material layer; an insulative element disposed between the two over-current and over-temperature protection elements for insulating the two over-current and over-temperature protection elements from each other; and a lateral conductive unit having a plurality of lateral conductive layers insulated from each other, wherein each lateral conductive layer is formed from top to bottom on lateral sides of one of the two over-current and over-temperature protection elements, the insulative element, and the other over-current and over-temperature protection element in sequence, and each lateral conductive layer is electrically connected with one of the power input portions or one of the power output portions.