Though its popularity has waned, the PLCC package was once a high-volume package in the industry. Developed in 1978 as a pre-molded package, Texas Instruments later developed a post-molded package that became widely adopted. In 1981, the JEDEC trade group created a task force to categorize PLCC body sizes. The JEDEC standard outline for square packages (MO-047) was released in 1984, and the rectangular package (MO-052) in 1985.

The PLCC package was quickly adopted due to its improvements over the previous SOP and DIP packages. Leads on all four sides allowed for a higher IO count and circuit density. The “J-lead” design allowed for other advantages over leadless or gullwing devices. The “J-lead” design absorbed mechanical stress better than a gullwing device, leading to higher reliability. This made it a common package used in higher reliability environments such as automotive or aerospace applications. The “J-lead” had limitations where the lead width needed to be sufficient to support and handle the multi-step bending process. This limited the density of IOs on PLCCs, and most manufacturers had a maximum size of 84 leads. The “J-lead” added higher complexity to the trim and form process, causing additional tooling and engineering time to install and maintain.

As time passed, PLCCs were replaced by even higher pin count QFPs, where the lead pitch could be much tighter, or QFNs, which could be made cheaper without requiring an intricate trim and form process. As fewer devices were designed using the PLCC outline, manufacturing floor space for this package was phased out. This has left behind customers who are still reliant on the PLCC outline.

Rochester Electronics maintains assembly capability on PLCCs to ensure a continuing source for this package style. Our new equipment and tooling allow for low-to-medium volume production for commercial to automotive-grade products. Rochester assembles a full range of body sizes and lead counts of PLCC packages stateside at our Newburyport facility. Regardless of the PLCC requirement, Rochester delivers with confidence and quality.