Issue link: https://iconnect007.uberflip.com/i/1515637
68 DESIGN007 MAGAZINE I FEBRUARY 2024 bonding results in parallel. A homogeneous red color on the Prescale pressure measurement film shown in Figure 1 provides the result. If bonding is imbalanced, the developed color will also be uneven; adjust the bonder tool or stage until you achieve uniformity of color. Since Prescale will turn color with heat and pressure, confirm the color in short bonding time and low pressure. To confirm the condition of equip- ment, please do not use cushion materials. Preferred Layer Structure for Flex and Rigid Circuits Any circuitry running below the bonding lead is not desirable, and can prevent stable compression from the bonding head. Design Guidelines for Flex and Rigid PCBs An appropriate design is shown in Figure 3. e line width should not be too large. Figure 1: Prescale pressure measurement film can help operators address bonding imbalance issues. Figure 2: The preferred design (left), and not preferred (right). Alignment is critical. Figure 3: Example of an appropriate design.