Designing flex circuits for improved flex life

The findings and conclusions of the study described in this paper can be summarized as follows: 1. The conductor cracking of the initial design of the flex circuit is inherent in this design. 2. The redesign for increased stiffness of the flex circuit is an improvement by about a factor of two over the problematic initial design, but falls short of providing an adequate minimum flex life of 20 cycles. 3. The redesign for increased flexibility of the flex circuit has a flex life improvement by about a factor of 20 over the initial design and exceeds the minimum flex life requirement by at least a factor of four. 4. The above conclusions are supported by both analytical and experimental results, which are in excellent agreement with each other.