WO2017116544A1

WO2017116544A1 - Modular printed circuit board assembly

Info

Publication number: WO2017116544A1
Application number: PCT/US2016/059149
Authority: WO
Inventors: Thomas Brey
Original assignee: Continental Automotive Systems, Inc.
Priority date: 2015-12-30
Filing date: 2016-10-27
Publication date: 2017-07-06

Abstract

A modular printed circuit board ("PCB") assembly including: a first PCB module having interlocking mating tabs; a second PCB module having interlocking mating slots interlocked with the plurality of interlocking mating tabs thereby mating the first PCB together, both mechanically and electrically, with the second PCB. The mating tabs and slots may be generally triangular shaped. The first and second PCB modules may be of different types, such as, for example, single sided, double sided, multi-layer, gold-plated, and high-density interconnect ("HDI"). A thermally activated Kapton adhesive tape may be applied to the plurality of interlocked mating tabs and slots.

Description

MODULAR PRINTED CIRCUIT BOARD ASSEMBLY

BACKGROUND

[0001] Embodiments of the invention are directed to a modular printed circuit board assembly comprising different types of printed circuit boards fastened together.

[0002] As is known in the art, a printed circuit board (PCB) mechanically

supports and electrically connects electronic

components using conductive tracks, pads, and other features etched from copper sheets laminated onto a non-conductive substrate. PCBs can be single sided (one copper layer), double sided (two copper layers) or multi-layer (outer and inner layers). Multi-layer PCBs allow for much higher component density. Conductors on different layers are connected with plated-through holes called vias. Advanced PCBs may contain components - capacitors, resistors or active devices - embedded in the substrate.

[0003] Certain applications, such as an automotive head unit faceplate, for

example, may have different sections to which different types of PCBs are better suited than other types of PCBs. For such applications, modular PCBs that can be mated together (e.g., in a way similar to pieces of a jigsaw puzzle) to form a modular PCB assembly before electronic component placement onto the modular PCB assembly would be an improvement, which would provide cost savings that would otherwise be unavailable.

BRIEF SUMMARY

[0004] In accordance with embodiments of the invention, a modular printed

circuit board ("PCB") assembly includes : a first PCB module having interlocking mating tabs! a second PCB module having interlocking mating slots interlocked with the plurality of interlocking mating tabs thereby mating the first PCB together, both mechanically and electrically, with the second PCB. The mating tabs and slots may be generally triangular shaped. The first and second PCB modules may be of different types, such as, for example, single sided, double sided, multi-layer, gold-plated, and high-density interconnect ("HDI"). A thermally activated Kapton adhesive tape may be applied to the plurality of interlocked mating tabs and slots.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 depicts PCB modules in accordance with embodiments of the

invention.

[0006] Figure 2 is a top view of the PCB modules of Figure 1.

[0007] Figure 3 is a bottom view of the PCB modules of Figure 1.

[0008] Figure 4 is a bottom view of the PCB modules of Figure 1 mated together.

[0009] Figure 5 is similar to Figure 4 and shows a thermally activated Kapton adhesive tape applied to the second side reflow or back side.

[0010] Figure 6 is cross -sectional view along view lines 6-6 in Figure 5.

[0011] Figure 7 is similar to Figure 1 and shows the PCB modules mated together into a modular PCB assembly in accordance with embodiments of the invention.

[0012] Figure 8 depicts two generally triangular-shaped interlocking mating tabs fit into two generally triangular-shaped interlocking mating slots with plate contact jumpers being used to join two PCB modules.

DETAILED DESCRIPTION

[0013] Embodiments of the invention are directed to combining different types of

PCB technologies together onto a single PCB assembly before placing electronics components onto the PCB assembly. This allows for cost- optimization with respect to the types of PCBs used in a final product. For example, for an automotive head unit face plate, the entire PCB does not need to be gold plated, just the areas that are used for button contacts. The intent of this concept is a solution that allows for standard factory processing after the PCB modules are mated together to form a modular PCB assembly.

[0014] Figure 1 depicts PCB modules 102, 104, and 106 in accordance with

embodiments of the invention. PCB modules 102 and 106 may be layer gold plated PCBs. These boards are intended to be used for the head-unit interface buttons.

[0015] PCB module 104 may be 8 layer High Density Interconnect ("HDI" PCB, which is as a PCB with a higher wiring density per unit area than conventional PCB. HDI PCBs have finer lines and spaces, smaller vias and capture pads, and higher connection pad density than employed in conventional PCB technology. By using 2 -layer gold-plated PCB sections, thereby not making the whole PCB HDI, cost savings may be realized.

[0016] Keying features for mating PCB modules together are also shown in

Figure 1. Generally triangular-shaped interlocking mating tabs 110 and generally triangular-shaped interlocking mating slots 108 are shown. Ten of each are shown in Figure 1, but only one of each is labeled with a corresponding reference number to keep Figure 1 uncluttered. Other suitable shapes for interlocking mating tabs and slots may also be used.

[0017] Figure 2 is a top view of the PCB modules of Figure 1.

[0018] Figure 3 is a bottom view of the PCB modules of Figure 1.

[0019] Figure 4 is a bottom view of the PCB modules of Figure 1 mated together.

The PCB's modules may be joined together by using the keying features, which are similar to those of jigsaw puzzle piece, with the generally triangular-shaped interlocking mating tabs 110 fitting into the generally triangular-shaped interlocking mating slots 108. Such an arrangement may be used to lock the PCB modules together in the X and Y directions, as shown in Figure 4. This also hnes up the pad locations that may be used to make electrical connections between the PCB modules.

[0020] Figure 5 is similar to Figure 4 and shows a thermally activated Kapton adhesive tape 502 applied to the second side reflow or back side.

[0021] Figure 6 is cross -sectional view along view lines 6-6 in Figure 5. The

thermally activated Kapton adhesive tape 502 provides support in the Z direction as shown in Figure 6. Other suitable adhesive materials may also be used. The material that is chosen may be low profile so as not to affect paste screening. As shown in Figure 6, the two PCB's may be coplanar.

[0022] Figure 7 is similar to Figure 1 and shows the PCB modules mated together into a modular PCB assembly 702 in accordance with embodiments of the invention. The Modular PCB assembly, once the PCB modules have been mated together, may be treated as one piece PCB for subsequent manufacturing processes. For example, the board's top side may then go through standard assembly processing (e.g, surface mounting of electronic components, and the like).

[0023] Figure 8 depicts two generally triangular-shaped interlocking mating tabs

110 fit into two generally triangular-shaped interlocking mating slots 108 with plate contact jumpers being used to join two PCB modules, thereby providing an additional Z-axis (as shown in Figure 6) constraining feature.

[0024] While the present invention has been illustrated by a description of

various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative example shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.

Claims

1. An apparatus comprising:

a first printed circuit board ("PCB") module having a plurality of interlocking mating tabs;

a second PCB module having a plurality of interlocking mating slots interlocked with the plurality of interlocking mating tabs thereby mating the first PCB together, both mechanically and electrically, with the second PCB to form a modular PCB assembly.

2. The apparatus of claim 1, wherein:

the first PCB module is of a type selected from the group of: single

sided, double sided, multi-layer, gold-plated, and high-density interconnect ("HDI"); the second PCB module is of a type selected from the group of: single sided, double sided, multi-layer, gold-plated, and high-density interconnect

("HDD; and

the first PCB module is of a different type than the second PCB module.

3. The apparatus of claim 1, wherein the modular PCB assembly is configured for use in an automotive head unit.

4. The apparatus of claim 1, further comprising: a thermally activated Kapton adhesive tape applied to the plurality of interlocked mating tabs and slots.

5. The apparatus of claim 1, wherein the first and second PCB modules are co-planar.

6. The apparatus of claim 1, further comprising plate contact jumpers used for joining the first and second PCB modules.

7. The apparatus of claim 6, wherein the plate contact jumpers provide a Z-axis constraining feature.

8. The apparatus of claim 1, wherein the plurality of interlocked mating tabs and slots are generally triangular shaped.