# Patent

## Title
Three dimensional substrate for hearing assistance devices

## Abstract

A hearing assistance device for a user comprising a housing, a three dimensional electronic substrate disposed in the housing, the substrate adapted to conform to a battery of the hearing assistance device and hearing assistance electronics mounted to the substrate.

## Background
PRIORITY APPLICATION
This application is a continuation of and clams the benefit of priority to U.S. patent application Ser. No. 12/340,591, filed Dec. 19, 2008, now issued as U.S. Pat. No. 8,737,658, which application is incorporated herein by reference in its entirety.


FIELD
The present subject matter relates to hearing assistance devices and more particularly to three dimensional substrates for hearing assistance devices.
BACKGROUND
Hearing assistance device manufacturers, including hearing aid manufacturers, have adopted thick film hybrid technologies that build up layers of flat substrates with semiconductor die and passive electronic components attached to each substrate using either surface mount, flip-chip, or wire-bond technologies that interconnect the various die. Conductors such as wires or flex circuits are attached to pads on the hybrid module after the hybrid module is assembled and tested. The conductors connect various electro-mechanical, electro-acoustical and electro-chemical devices to the active electronics within the hybrid. Connection points may be provided for a battery, receiver/speaker, switch, volume control, microphones, programming interface, external audio interface and wireless electronics including an antenna. Recent advances, such as the addition of wireless technology, have stressed designers' ability to accommodate additional advances using expanded hybrid circuits because of size limitations within a device housing. Growing the hybrid to add features, functions and new interfaces, increases the overall size and complexity of a hearing instrument. Expanding the current hybrid may not be a viable option since the hybrid circuit is made up of finite layers of rectangular plains. The larger, complex circuits compete with most manufacturer's goal of small and easy to use hearing assistance devices.
SUMMARY
The above-mentioned problems and others not expressly discussed herein are addressed by the present subject matter and will be understood by reading and studying this specification. The present subject matter relates to a hearing assistance device for a user comprising a housing, a substrate disposed in the housing, the substrate adapted to conform around a battery of the hearing assistance device, and hearing assistance electronics mounted to the substrate. Various embodiments include, but are not limited to, embodiments where the substrate is adapted to structurally receive the battery, embodiments where the substrate is adapted to conform around a battery compartment, and embodiments where the substrate is adapted to connect to contacts integral to a battery compartment. Various designs include, but are not limited to, substrates with integral antennae. The embodiments include a variety of hearing assistance device applications and housings, such as an in-the-canal hearing aid, an in-the-ear hearing aid, a completely-in-the-canal hearing aid, a behind-the-ear hearing aid, and a receiver-in-the-canal hearing aid.
This Summary is an overview of some of the teachings of the present application and not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details about the present subject matter are found in the detailed description and appended claims. The scope of the present invention is defined by the appended claims and their legal equivalents.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a three dimensional (3D) substrate and hearing assistance electronics according to one embodiment of the present subject matter.
FIG. 2 shows a 3D substrate according to one embodiment of the present subject matter.
FIG. 3 shows a hearing assistance device with a 3D substrate according to one embodiment of the present subject matter.
FIGS. 4A-C show various views of a partially assembled 3D substrate according to one embodiment of the present subject matter.
FIG. 5 shows an assembled 3D substrate installed in a hearing aid faceplate according to one embodiment of the present subject matter.



DETAILED DESCRIPTION
The following detailed description of the present subject matter relates to the accompanying drawings which show, by way of illustration, specific aspects and embodiments in which the present subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present subject matter. References to “an”, “one”, or “various” embodiments in this disclosure are not necessarily to the same embodiment, and such references contemplate more than one embodiment. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope is defined only by the appended claims, along with the full scope of legal equivalents to which such claims are entitled.
In various embodiments, the 3D substrate defines a battery compartment for a hearing assistance device and provides structural rigidity to support a battery or other power source, such as a super capacitor for example. In some embodiments, the 3D substrate is formed from a flexible substrate with contacts which is wrapped around a battery compartment (for example, a battery drawer assembly designed to mechanically hold the battery). In such designs, the contacts can be arranged for direct connection to the battery or other power source. In some embodiments, the battery compartment includes battery contacts which are rigidly mounted to the compartment. In such designs, the 3D substrate wraps around the battery compartment and makes contact with the battery contacts of the battery compartment. In some embodiments, a gasket is used to form a water resistant or moisture resistant seal for the battery compartment. Other seals, including, but not limited to, glues and rubber or polymer seals may be employed to form water resistant or moisture resistant seals without departing from the scope of the present subject matter. The 3D substrate can be used with a variety of hearing assistance device housings including, but not limited to, behind-the-ear, in-the-ear, on-the-ear, in-the-canal and completely-in-the-canal housings, as well as housings used for receiver-in-the-canal and cochlear implant applications. Other variations are possible without departing from the scope of the present subject matter.
FIG. 1 shows a three dimensional (3D) substrate 100 and hearing assistance electronics 101 according to one embodiment of the present subject matter. The 3D substrate includes contours that form internal housing surfaces of a hearing assistance device. The illustrated embodiment shows a 3D substrate 100 that conforms to a battery for a hearing assistance device. The 3D substrate 100 provides surfaces for mounting electronics 101 in areas, such as around a battery, where mounting a flat, thick film substrate and attached electronics are not possible. Examples of electronics mounted to the 3D substrate include, but are not limited to, active electronics, passive electronics, digital electronics, analog electronics or combinations thereof.
In various embodiments, a standard 3D substrate is used for custom, physically fitted hearing assistance devices. The 3D shape of the substrate is developed from digital imaging data of multiple custom hearing assistance devices such that a standard 3D substrate takes into account extreme space restrictions of a population of custom, physically fitted hearing assistance devices. Although the standard 3D substrate may not accommodate every custom, physically fitted hearing assistance device, it reduces the custom electronic assembly of at least a portion of the demand, thus reducing cost and, in turn, increasing access to custom fitted devices.
FIG. 2 shows a 3D substrate 210 according to one embodiment of the present subject matter. The 3D substrate 210 includes integrated conductive elements 211 for connecting electronic components 212 to the substrate and interconnecting the electronic components. The integrated conductive elements provide, among other things, interconnection of components, isolation of circuits, and shielding and grounding planes to improve performance. The integrated conductive elements 211 include, but not limited to, traces, mounting pads and wire bonding pads. The conductive elements 211 are integrated with the substrate using methods including printing and plating. Other methods of integrating conductive elements with the 3D substrate are possible without departing from the scope of the present subject matter. In various embodiments, the substrate includes areas for mounting and connecting other electro-mechanical, electro-chemical and accessory devices including, but not limited to, receivers, wiring harnesses for remote receivers such as a receiver for wearing in an ear canal, microphones, switches, interface connectors, antennas, battery contacts or combinations thereof.
Electronic components of the hearing assistance device are mounted to and distributed about the 3D substrate. The technology allows more efficient use of the interior space of the hearing assistance device. In various embodiments, a 3D substrate provides mounting surfaces and interconnections for multiple features of a hearing assistance device. Upon assembly, only the electronics supporting the features ordered for that device are mounted and connected. In some embodiments, the 3D substrate only provides mounting areas for limited features. In some embodiments, allowing only limited features provides additional volume within the housing of the hearing assistance device to provide other features or expand existing features. For example, a 3D substrate may not provide space for wireless electronics, but accommodates additional memory. In some embodiments, the 3D substrate is used with flexible circuit technology. For example, a flexible circuit substrate 213 is used to mount and interconnect electronics 212, such as an ASIC die. The flexible circuit 213 is then mounted and connected to the 3D substrate 210 for interconnection to other hearing assistance electronics 212.
In various embodiments, the hearing assistance device includes a 3D substrate and wireless communication electronics. An antenna for transmitting, receiving or transmitting and receiving data with the wireless electronics is integrated with the 3D substrate. In some embodiments, the antenna is integrated along a perimeter area of the substrate or where there is sufficient room. In some embodiments, the integrated antenna follows the contours of the 3D substrate. In some embodiments, the antenna is inserted in a groove on a faceplate mounting surface to provide mounting stability and rigidity to the 3D folded substrate.
FIG. 3 shows a hearing assistance device with a 3D substrate according to one embodiment of the present subject matter. The hearing assistance device 320 includes a shell 321, faceplate 322, 3D substrate 323 and a battery door assembly 324, The 3D substrate 323 defines a battery well 325 and an area for mounting a microphone 326 and providing access to a microphone port 327 in the battery door assembly 324. The 3D substrate 323 includes hearing assistance electronics 328 mounted to the 3D substrate 323. A microphone 326 is mounted to the substrate 323 and electrically connected to the hearing assistance electronics 328. Conductive elements, including traces and bonding pads, are integrated with the 3D substrate 323 to interconnect the hearing electronics 328 and the microphone 326. In various embodiments, the 3D substrate includes integrated battery contacts for connecting a battery to the hearing assistance electronics.
During assembly, the 3D substrate 323 extends into the hearing assistance device shell 321 through an opening in the faceplate 322. In various embodiments, the substrate 323 includes a lip 329 that attaches to and seals the opening in the faceplate 322. The faceplate 322 is attached to the hearing assistance device shell 321. In some embodiments, the lip 329 provides a watertight seal for a waterproof hearing assistance device 320. In various embodiments, the 3D substrate is rigid. In some embodiments, a gasket is used to form a water resistant or moisture resistant seal for the battery compartment. Other seals, including, but not limited to, glues and rubber or polymer seals may be employed to form water resistant or moisture resistant seals without departing from the scope of the present subject matter.
In the illustrated embodiment, a speaker 330 is connected to the 3D substrate 323. The speaker is positioned at or near a speaker opening 331 in the shell 321 to play sounds to a user's ear. In some embodiments, the speaker 330, or receiver in the case of a hearing aid, is mounted and electrically connected to the 3D substrate 323 and the hearing assistance electronics 328. In various embodiments, a programming port is electrically connected to the hearing electronics mounted on the 3D substrate. In some embodiments, the programming port is mounted to the 3D substrate. It is understood that other electronic components mounted to and/or connected to the 3D substrate are possible without departing from the present subject matter. Examples of other electronic components include, but are not limited to, switches, visual indicators, volume controls, mode selectors or combinations thereof. The 3D substrate can be used with a variety of hearing assistance device housings including, but not limited to, behind-the-ear, in-the-ear, on-the-ear, in-the-canal and completely-in-the-canal housings, as well as housings used for receiver-in-the-canal and cochlear implant applications.
FIGS. 4A-C show various views of a partially assembled 3D substrate 440 according to one embodiment of the present subject matter. FIG. 4A shows a plan view of the component or exterior side of the 3D substrate. FIG. 4C shows the interior side of the 3D substrate. FIG. 4B shows a side view of the substantially flat partially assembled 3D substrate. The 3D substrate includes various electrical components 442 assembled to a foldable substrate 441 and form at least a portion of the hearing assistance electronics for a hearing assistance device. The electronic components 442 include both active and passive components interconnected using conductive traces integrated with the foldable substrate 441. Upon further assembly, the substrate 441 is folded into a 3-dimensional shape. Various slots 443 and tabs 444 are engaged to add structural integrity to the 3D substrate 440 and to maintain the folded shape. The 3D substrate includes various contact areas for connecting to other hearing assistance device components including but not limited to, microphones 445, speaker 446, telecoil 447, battery 448, an external programmer interface 449, controls 451, 452 such as switches and dials or combinations thereof. Methods of connecting components to the contact areas of the substrate include, but are not limited to, solder, compression connections, direct contact and combinations thereof. It is understood that other methods for connecting components to the contact areas of the substrate are possible without departing from the scope of the present subject matter. In various embodiments, the substrate includes an antenna 450 for wireless communications. In one embodiment, the antenna 450 is integrated along a perimeter area of the substrate.
In various embodiments, the substrate 441 is made of a flexible material including, but not limited to, Liquid Crystal polymer (LCP), polyphtalamide (PPA), Teflon, thin plated plastic or combinations thereof. In some embodiments, the substrate is in a rigid 3D form using plated plastic or ceramic. In various embodiments, the substrate is fabricated in an flat, arrayed format using traditional injection molding processes. After the arrayed parts are molded, conductive traces are integrated with the substrate. In one embodiment, forming the conductive traces includes metalizing the parts with a conductive layer, such as copper, applied to one or more of the substrate surfaces. The desired conductive pattern is then laser cut into the metallization. A chemical process is used to etch away undesired metalized regions. Desired metalized areas are plated. Plating materials include, but are not limited to, nickel, gold or a combination thereof. The arrays are separated into individual parts. Electronics are assembled onto the individual parts and the parts are tested. Having the substrate in a flat configuration, as opposed to a 3D form, allows for more efficient assembly of the electronics to the substrate and also simplifies subsequent testing. In various embodiments, one or more electronic components may be added and tested before the arrayed parts are separated. It is understood that other materials and processes for forming and assembling the substrate are possible without departing from the scope of the present subject matter.
FIG. 5 shows an assembled 3D substrate 570 installed in a hearing aid faceplate 571 according to one embodiment of the present subject matter. The 3D substrate 570 is folded to define a battery cavity within an opening in the hearing aid faceplate 571. The shape of the folded substrate is retained using mated slots and tabs 572. The substrate includes hearing assistance electronics 573 distributed about at least the exterior of the defined battery cavity in areas normally not conducive to placement of electronics. The 3D substrate includes contact pads 574 for connecting to a microphone 575 inserted through the opening in the hearing aid faceplate 571. In various embodiments, the 3D substrate includes contact pads for electrically connecting other electronic components to the hearing assistance electronics including, but not limited to, a speaker, wiring harnesses, switches, visual indicators, volume controls, mode selectors or combinations thereof. The 3D substrate includes contact pads 576 for electrically connecting a battery 577 with the hearing aid electronics 573 using direct contact. In various embodiments, the 3D substrate 570 includes wireless electronics for wireless RF or inductive communications. The wireless electronics connect to an antenna 578 integrated with the 3D substrate. The antenna 578 is inserted in a groove on the faceplate mounting surface to provide mounting stability and rigidity to the 3D folded substrate. In some embodiments, the flex antenna loop floats so that it fills the inside shape of the shell and can maximize aperture using variations in the shape of each shell. In various embodiments, the antenna includes conductive traces integrated with the faceplate and connected to the wireless electronics of the 3D substrate.
The 3D substrate can be used with a variety of hearing assistance device housings including, but not limited to, behind-the-ear, in-the-ear, on-the-ear, in-the-canal and completely-in-the-canal housings, as well as housings used for receiver-in-the-canal and cochlear implant applications. Use of a 3D substrate provides opportunities to make more efficient use of space inside of a hearing assistance device. In some examples, use of a 3D substrate takes advantage of traditionally unusable space within a hearing assistance device housing for additional electronics that in turn can provide increased processing power, additional features, additional memory or combinations thereof.
This application is intended to cover adaptations and variations of the present subject matter. It is to be understood that the above description is intended to be illustrative, and not restrictive. The scope of the present subject matter should be determined with reference to the appended claim, along with the full scope of legal equivalents to which the claims are entitled.

## Claims

1. A hearing assistance device, comprising:
a three-dimensional folded substrate including contours configured to form internal housing surfaces of the hearing assistance device, wherein the substrate included a plurality of slots and tabs configured to be engaged to add structural integrity to the substrate and maintain the folded shape;
hearing assistance electronics mounted to a flat portion of the substrate; and
a moisture resistant seal for the substrate, the seal configured to limit moisture ingress into the device.

2. The device of claim 1, wherein the moisture resistant seal includes a gasket.

3. The device of claim 1, wherein the moisture resistant seal includes glue.

4. The device of claim 1, wherein the moisture resistant seal includes rubber.

5. The device of claim 1, wherein the moisture resistant seal includes a polymer.

6. The device of claim 1, whererin the substrate includes a liquid crystal polymer (LCP).

7. The device of claim 1, wherein the substrate structurally forms a battery compartment.

8. The device of claim 1, further comprising an antenna connected to the hearing assistance electronics.

9. The device of claim 1, further comprising an antenna integrated with the substrate.

10. The device of claim 1, wherein the housing is a behind-the-ear housing.

11. The device of claim 1 wherein the housing is an in-the-ear housing.

12. The device of claim 1, wherein the housing is an in-the-canal housing.

13. The device of claim 1, wherein the housing is a receiver-in-the-canal housing.

14. The device of claim 1, further comprising a microphone electrically connected to the substrate.

15. The device of claim 1, further comprising a speaker electrically connected to the substrate.