Flexible circuit boards offer numerous advantages. However, the mechanical fixation of these circuit boards is highly complex. Harting has developed a new approach based on 3D-MID technology that is capable of replacing flexible circuit boards. Thanks to component carriers, cost savings of up to two-thirds can be achieved.
Flexible printed circuit boards made of thin polyimide films have established themselves in many product areas thanks to their application flexibility. Populating and assembling them, however, is decidedly more complex. This is where a newly developed component carrier from Harting enters the picture.
By harnessing this all-new Harting development, electronic components can be fitted directly onto the component carrier, thereby replacing flexible circuit boards. The component carrier serves as a connecting element between the printed circuit board (PCB) and electronic components such as LEDs, ICs, photodiodes and sensors.
Electronic components are mounted directly on the new component carrier in automated processes. The frequently complex processes involved in processing flexible circuit boards is dispensed with, thereby reducing costs by up to two-thirds.
The populated component carriers are delivered in tape & reel. In their standard design, the carriers can be processed in automatic assembly systems, just like other SMD electronic components. Two different sizes are currently available and can accommodate electronic components of standard size SOIC-8 and smaller. Moreover, Harting can also produce the carriers in customer-specific sizes.
Harting has identified three example applications where the component carrier can replace flexible circuit boards:
Thanks to the 3D-MID (mechatronic integrated device) technology, electronic components can be fitted directly onto a three-dimensional body without the need for circuit boards or connecting cables. The base body is produced through injection moulding, whereby the thermoplastic is provided with a non-conductive, inorganic additive. In order for this material to be able to accommodate electrical circuits, the additives in the plastic are "activated" through laser direct structuring (LDS). In this process, the laser beam writes the areas intended for the conductive tracks and creates a micro-rough structure. The metal particles released in the process form the nuclei for the subsequent chemical metallisation.
This process creates electrical traces across the three-dimensional base body. The plastic employed offers high thermal stability and can therefore be soldered in the reflow oven. Harting has been implementing the entire 3D-MID process chain in-house for over 10 years, from the project idea to the populated series product. The technology is finding use in application scenarios in areas such as medical technology, industrial electronics and consumer electronics and all the way through to safety-related components in the automotive industry. The Harting 3D-MID business unit is the largest provider of 3D-MID components outside of Asia. The component carrier developed by this process is suitable for various applications. It can be equipped with several sensors that, if desired, could be aligned in three directions to take measurements in three axes (X, Y, Z). Components can be fitted simultaneously on two parallel surfaces on the front and back sides, as well as on the end face. Harting has submitted a patent application for the component carrier.
In an automated process, Harting fits electronic components such as LEDs, ICs, photodiodes and sensors directly on the component carrier. The total cost of the component carrier is two-thirds lower than those of flexible PCBs. This is because it eliminates the frequently complex handling involved with flexible printed circuit boards, e.g. populating, gluing and assembling. The process even delivers benefits in small volumes, as the component carrier can be used for different applications without adaptation, thereby eliminating the costs of a new injection mould. Compared with flexible printed circuit boards, this process achieves more precise component positioning, greater repeatability and better quality.
Harting has identified another advantage of the component carrier, namely the short timeframe required to deliver finished components. Since the plastic carrier remains unchanged, all that is needed are specifications for placement of the electronic components. Experts in 3D-MID can use this to create a production-optimised layout proposal. Adjustments of the laser program are all that is needed to tailor the electrical traces to the respective application. Once the customer has approved the product and components have been received, initial production samples can be dispatched within two to three weeks - and even faster, if necessary.
Learn more about the component carrier at www.harting.co.uk.