In a recent survey, we asked the following question: What are your biggest problems related to flex design? Here are a few of the answers, edited slightly for clarity.
1. We are lagging in technology.
2. None…design them correctly!
3. Stress cracking in FPC ZIF fingers.
4. We need to work more closely with our FPC fab vendors.
5. Signal integrity of signal paths through the flex and rigid parts of the PCB.