Abstract:
A hearing aid comprising a microphone, a receiver, hearing aid electronics coupled to the microphone and the receiver, and conductive traces overlaying an insulator, the conductive traces configured to interconnect the hearing aid electronics and to follow non-planar contours of the insulator. Examples are provided wherein the insulator includes a hearing aid housing.

Description:
PRIORITY AND RELATED APPLICATIONS 
       [0001]    The present application claims the benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application Ser. No. 61/087,899, filed Aug. 11, 2008, which is incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present subject matter relates generally to hearing assistance devices and housings and in particular to method and apparatus for integration of electrical components with hearing assistance device housings. 
       BACKGROUND 
       [0003]    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. Manufacturing of such circuits employ technologies, such as, surface mount, flip-chip, or wire-bond 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 electrochemical 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&#39; 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 planes. The larger, complex circuits compete with most manufacturers&#39; goals of small and easy to use hearing assistance devices and hearing aids. 
       SUMMARY 
       [0004]    The present subject matter relates to hearing aids comprising a microphone, a receiver, hearing aid electronics coupled to the microphone and the receiver and a conductive traces integrated with an insulator, the conductive traces adapted to interconnect the hearing aid electronics and to follow non-planar contours of the insulator. In some examples, the insulator includes a hearing aid housing and components of the hearing aid electronics embedded in the hearing aid housing. In some examples, the insulator includes a connector plug to connect a transducer to the hearing aid electronics. In some examples, the connector plug includes an embedded electrical device. 
         [0005]    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 subject matter is defined by the appended claims and their legal equivalents. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1A  illustrates a portion of a hearing assistance device housing according to one embodiment of the present subject matter. 
           [0007]      FIG. 1B  shows a three dimensional view of the COI technologies present in the hearing assistance device housing of  FIG. 1A  according to one embodiment of the present subject matter without the plastic housing portion. 
           [0008]      FIGS. 2A and 2B  demonstrate various views of a COI application for components according to one embodiment of the present subject matter. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    The following detailed description of the present invention refers to subject matter in 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. 
         [0010]    The present subject matter provides apparatus and methods for using conductor on insulator technology to provide space saving, robust and consistent electronic assemblies. Although applicable to various types of electronics and electronic devices, examples are provided for hearing assistance devices. In various applications, the insulator is a plastic. In various applications the insulator is a ceramic. Other insulators are possible without departing from the scope of the present subject matter. 
         [0011]      FIG. 1A  illustrates a portion  100  of a hearing assistance device housing  100  according to one embodiment of the present subject matter. The illustrated housing portion includes a number of conductor-on-insulator (COI) applications. Example applications of COI traces visible in  FIG. 1  are contact pads  101 ,  102  and multi axis traces  103 , connected to the contact pads  101 . The multi axis traces  103  follow the tight contours of the housing and eliminate the need for bonding wires, a separate substrate, or both, to connect, for example, a transducer or a switch, to the hearing assistance electronics. In various embodiments, electrical components, such as transducers, sensors switches and surface mounted electronics, connect to the contact pads  101 ,  102  using conductive silicone. Conductive silicone reduces the need for solder and makes the replacement and service of electrical components in the hearing assistance device more efficient. 
         [0012]    In the illustrated embodiment, portions of COI traces  105  lead to an integrated capacitor (see for example capacitor  108  on  FIG. 1B ). Integrating electrical components, such as passive components, with the housing of the hearing assistance device frees up area within the housing and provides additional design freedom to modify the size of the device or add additional features. It is understood that other integrated passive electrical components are possible without departing from the scope of the present subject matter. 
         [0013]    This approach also allows the integration of ball grid array component bond pads  106  and connecting traces  107  with the device housing as demonstrated in  FIG. 1A . The COI bond pads  106  and traces  107  reduce the need for an additional substrate and bond wires, thus freeing up space within the housing. Such designs can provide for one or more of: smaller housings, additional features, more streamlined manufacturing processes, and/or more consistent performance of the electronics of the device. 
         [0014]      FIG. 1B  shows a three dimensional view of the COI technologies present in the hearing assistance device housing of  FIG. 1A  without the plastic housing portion.  FIG. 1B  includes the multi axis traces  103  and bond pads  101 ,  102  integrated with the sidewalls of the housing.  FIG. 1B  also shows the position of the integrated capacitor  108  discussed above and the traces  105  connected to the capacitor. Additional bonding pads  106  for a ball grid array (BGA) component or other surface mounted electronics are illustrated in  FIG. 1B .  FIG. 1B  demonstrates some additional options for design, including, but not limited to, an active component  109  integrated into the device housing, a large bonding pad  110  and distribution trace  111  for a battery, and an inter-cavity conductor  112  and contact pad  113 . In one embodiment, active component  109  is a flip chip semiconductor die. Other design options are possible, and those shown herein are intended to demonstrate only some options and are not intended to be an exhaustive or exclusive set of design options. 
         [0015]      FIGS. 2A and 2B  demonstrate various views of a COI application for components. In the example of  FIGS. 2A and 2B  a plug for a hearing assistance device is coated with conductive traces. In one embodiment, the plug is used with a receiver-in-the-canal (RIC) application, such as RIC plug  220 . The plug includes a number of conductive traces  221  integrated with the plastic body  222 . The illustrated plug is used to connect an OTE or BTE type housing to a RIC device. In this embodiment, the plug includes five ( 5 ) traces  221  and contact pads  224  to connect both a receiver (2 traces) and a microphone (3 traces). In the design shown, discrete components, such as a DC blocking capacitor  223  is integrated with the body of the plug. Available space of the plug is better utilized by embedding the passive component  223 , in this example a microphone DC blocking capacitor. Integrating components, such as surface mounted electronics, into the plug body frees up volume within the housing of the hearing assistance device. The component  223  can be placed into a cavity with a connector or can be otherwise integrated into the connector using a variety of technologies. The capacitor  223  can either be placed into a cavity within a connector or the capacitor can be completely embedded within the connector using various technologies known in the art. For example, a technology called Microscopic Integrated Processing Technology (MIPTEC) available from Panasonic integrates 3-dimensional conductive elements about the surface of various injection molded components. The process includes molding one or more articles, thinly metalizing one or more surfaces using sputter deposition, for example, laser etching conductor patterns in the metallization layer, electroplating the conductors with copper, etching to remove excess metallization material and then electroplating additional conductive material such as nickel and aluminum to form the finished conductors. The process is used to form 3-dimensional conductive traces on plastic and ceramic insulators. Additional technologies, including various Molded Interconnect Device (MID) technologies, are available for integrating and embedding electrical circuit and circuit components with a housing, including, but not limited to, the process described in U.S. Patent Publication 2006/0097376, Leurs, et al., and incorporated by reference herein in its entirety. 
         [0016]    Referring again to  FIGS. 2A and 2B , in various embodiments, a hearing assistance system includes two plugs. One plug connects wires to the receiver, or RIC device, and the other connects the wires to the housing enclosing the hearing assistance electronics. In various embodiments, conductive silicone is used to electrically connect the plug with the corresponding circuits in a mated connector. 
         [0017]    For hearing assistance devices, COI technology provides some benefits including, but not limited to, one or more of: tightly controlled and consistent radio frequency (RF) characteristics due to consistent circuit placement; reduced feedback and/or repeatable feedback performance due to precise transducer lead location; efficient production with substantially fewer manufacturing steps including elimination of manual soldering, wire routing, and related, traditional electronic assembly operations, smaller hearing instruments; possible elimination of wires; possible elimination of the traditional PCB or thick film ceramic substrate; and possibly smaller and/or less expensive hearing instrument components. Such components include, but are not limited to RIC connectors, DAI modules, capacitive switches, or antenna modules. 
         [0018]    Examples of hearing assistance device designs benefiting from COI technologies include, but are not limited to, behind-the-ear (BTE) and over-the-ear (OTE) designs as well as the faceplates of in-the-ear (ITE), in-the-canal (ITC) and completely-in-the-canal (CIC) designs. Any hearing assistance device housing and/or connectors can benefit from the teachings provided herein. In a hearing assistance device housing, for example, DSP, memory, and RF semiconductor dies can be flip chip attached and integrated with the hearing instrument housing or spine along with passive components, battery contacts, interconnecting conductor traces, RF antenna, and transducer connectors to reduce the assembly process of the hearing assistance device. 
         [0019]    It will be understood by those of ordinary skill in the art, upon reading and understanding the present subject matter that COI technology includes, but is not limited to, conductor-on-plastic (COP) or conductor-on-ceramic (COC) processes, for example. Technologies have been developed, as discussed above, which enable formation of conductive patterns either on or embedded within uniquely shaped plastic or ceramic substrates. Such processes facilitate production of electronic assemblies or components integrated with uniquely shaped plastic or ceramic substrate structures. 
         [0020]    The present subject matter includes hearing assistance devices, including, but not limited to, cochlear implant type hearing devices, hearing aids, such as behind-the-ear (BTE), in-the-ear (ITE), in-the-canal (ITC), or completely-in-the-canal (CIC) type hearing aids. It is understood that behind-the-ear type hearing aids may include devices that reside substantially behind the ear or over the ear. Such devices may include hearing aids with receivers associated with the electronics portion of the behind-the-ear device, or hearing aids of the type having receivers in-the-canal. It is understood that other hearing assistance devices not expressly stated herein may fall within the scope of the present subject matter. 
         [0021]    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 equivalents to which the claims are entitled.