Fusible flexible printed circuit and method of making same

Abstract

A fusible flexible printed circuit includes one or more conductors extending along a flexible dielectric substrate. Each conductor is comprised of a layer of electrically conductive material and a layer of fusible material extending along part or all of said conductive layer. One or more gaps is formed in the conductive layer at location opposite a segment of the fusible layer so that electrical current flowing through each conductor is required to pass in its entirety through the layer of fusible material at the location of each gap in the layer of conductive material. The integral fuses are designed to specific electrical parameters and may be located randomly along circuit runs. Preferably, the circuit is reinforced at the locations of the fuses by metal support strips designed to minimize motion stress on the fuses and the fuses are sealed within bubbles in a protective overlay which capture debris when the fuses are blown. The use of such a circuit to incorporate a variety of fuses having different fuse ratings into the conductive paths of a flexible printed circuit is also disclosed, as is a method of making the fusible circuit.