Implant and method for producing an implant

Abstract

The disclosure relates to an implant comprising an electrode connection device and a housing, wherein a cover for closing the housing is formed on the electrode connection device. A method for producing an implant is also disclosed.

Claims

1. An implant comprising: an electrode connection device; and a housing, wherein a cover for closing the housing is formed on the electrode connection device, wherein the electrode connection device has a preassembled assembly, wherein the assembly comprises: a continuous receiving means for a male connector, a first connection element, which is arranged in a front region of the receiving means, wherein the first connection element has at least two flat side faces, and a second connection element, which is arranged in a rear region of the receiving means, wherein the second connection element has at least two flat side faces, wherein the assembly is surrounded at least in some sections by a plastic, and wherein a first guide for a first conductor for connection to a connection region of the first connection element is formed in the plastic, and/or wherein a second guide for a second conductor for connection to a connection region of the second connection element is formed in the plastic.

2. The implant according to claim 1, wherein the cover is welded to the housing.

3. The implant according to claim 1, wherein a welding protection means is formed on the cover.

4. The implant according to claim 1, wherein the cover is formed from a biocompatible material.

5. The implant according to claim 1, wherein the cover and the housing are formed from the same material.

6. The implant according to claim 1, wherein a feedthrough is formed in the cover, wherein the feedthrough forms an electrical connection between the electrode connection device and an electronics module arranged in the housing.

7. The implant according to claim 6, wherein the feedthrough is electrically connected to a plug-in connection or to a spring contact with the electronics module.

8. The implant according to claim 1, wherein the first guide is formed adjacently to the connection region of the first connection element, and/or wherein the second guide is formed adjacently to the connection region of the second connection element.

9. The implant according to claim 1, wherein a positioning means is formed at a rear end of the receiving means.

10. The implant according to claim 1, wherein the assembly also has a further receiving means for a further male connector, wherein a third connection element is arranged in a front region of the further receiving means, and wherein a fourth connection element is arranged in a rear region of the further receiving means.

11. A method for producing an implant, comprising the following steps: providing a housing, providing an electrode connection device, wherein a cover for closing the housing is formed on the electrode connection device, arranging the cover on the housing, and connecting the cover to the housing, wherein the electrode connection device has a preassembled assembly, wherein the assembly comprises: a continuous receiving means for a male connector, a first connection element, which is arranged in a front region of the receiving means, wherein the first connection element has at least two flat side faces, and a second connection element, which is arranged in a rear region of the receiving means, wherein the second connection element has at least two flat side faces, wherein the assembly is surrounded at least in some sections by a plastic, and wherein a first guide for a first conductor for connection to a connection region of the first connection element is formed in the plastic, and/or wherein a second guide for a second conductor for connection to a connection region of the second connection element is formed in the plastic.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Exemplary embodiments are explained in more detail below with reference to the figures, in which:

(2) FIG. 1 shows a schematic representation of an implant according to the prior art,

(3) FIG. 2 shows an exploded view of an embodiment of an implant according to the present invention,

(4) FIG. 3 shows a perspective view of a part of the implant according to FIG. 2,

(5) FIG. 4 shows a side view of an implant,

(6) FIG. 5 shows a detail of the electronics module,

(7) FIG. 6 shows a further detail of the electronics module,

(8) FIG. 7 shows a block diagram of the implant according to the present invention,

(9) FIG. 8 shows a side view of the electronics module (upper image of FIG. 8), a view of the electronics module from below (middle image of FIG. 8) and a view of the electronics module from above (lower image of FIG. 8),

(10) FIG. 9 shows a perspective view of the top side of the electronics module (upper image of FIG. 9) and a perspective view of the underside of the electronics module (lower image of FIG. 9),

(11) FIGS. 10A-10E show a production process for the electronics module,

(12) FIG. 11 shows a perspective view of an embodiment of an assembly for an electrode connection device,

(13) FIG. 12 shows a front view (upper image of FIG. 12) and a rear view (lower image of FIG. 12) of the assembly according to FIG. 11,

(14) FIG. 13 shows the assembly according to FIGS. 11 and 12 with potting aids,

(15) FIG. 14 shows the assembly according to FIGS. 11 to 13 with an antenna and conductors,

(16) FIG. 15 shows the assembly according to FIGS. 11 to 14 arranged on a housing,

(17) FIG. 16 shows the assembly according to FIGS. 11 to 15 completely potted (with potting aids),

(18) FIG. 17 shows the assembly according to FIGS. 11 to 15 completely potted (without potting aids), and

(19) FIG. 18 shows another embodiment of an implant according to the present invention.

DETAILED DESCRIPTION

(20) FIG. 2 shows an embodiment of an implant according to the present invention. The implant comprises a two-part housing 60 with a first housing shell 60a and a second housing shell 60b. An electronics module 61 and an energy store 62 (for example a battery) are arranged in the housing 60. The energy store 62 is electrically insulated from the housing 60 by means of an insulating cover 64. The electronics module 61 is arranged on a front side 68 of the energy store 62. A first pin element is arranged on the front side 68 of the energy store 62 and comprises two pins 66a, 66b oriented parallel to each other. Associated with the first pin element is a first pin receptacle which comprises two ring-shaped pin receptacles 67a, 67b and which is arranged on the electronics module 61. By means of the first pin element 66a, 66b and the first pin receptacle 67a, 67b, an electrical connection is formed between the energy store 62 and the electronics module 61. The electronics module 61 is connected to a feedthrough 65. Details of the connection are explained in greater depth below. An electrode connection device 63 is arranged on the housing 60 and is connected to the electronics module 61 by means of the feedthrough 65.

(21) The feedthrough 65, the electronics module 61 and the energy store 62 are assembled along an axis (here along the z-direction). The direction of the axis is determined by the direction of the electrical connection between the feedthrough 65 and the electronics module 61 and the electrical connection between the electronics module 61 and the energy store 62.

(22) In the embodiment shown, the electronics module 61 is arranged parallel to the front side 68 of the energy store 62. This type of arrangement uses the space in the housing very efficiently. The electronics module 61 may be plugged onto the front side 68 of the energy store 62 and/or glued to the front side 68.

(23) In FIG. 3, the elements of the implant are partially assembled. The electronics module 61 is fitted on the energy store 62. Furthermore, the feedthrough 65 is connected to the electronics module 61. The energy store 62 (in the insulating cover 64) with the electronics module 61 is arranged in the second housing shell 60b. In the next step, the first housing shell 60a is arranged on the second housing shell 60b and the housing shells 60a, 60b are joined together, for example welded (not shown). Subsequently, the electrode connection device 63 is placed on the housing 60 and connected to the feedthrough 65 (not shown).

(24) FIG. 4 shows a side view of an implant that corresponds substantially to the implant in FIG. 2. Like elements are therefore designated by like reference signs. In the embodiment according to FIG. 4, the electronics module 61 is arranged in a support frame 69. The support frame 69 is arranged on the front side of the energy store 62. The support frame 69 serves to centre the energy store 62 in the housing 60 and presses it against the housing base. This prevents the transmission of vibrations as well as compressive and tensile forces. The support frame 69 thus protects the components on the electronics module 61 as well as the electrical connection between the energy store 62 and the electronics module 61 from destruction and/or loss of electrical contact.

(25) A detail of the electronics module 61 is shown in FIG. 5 (the lower part of FIG. 5 shows an enlarged detail of the upper part). The feedthrough 65 is formed as a multi-pole feedthrough with a plurality of pins 70. In the embodiment shown, five pins 70 are formed on the feedthrough 65, but a different number of pins is also possible. Each pin 70 is inserted into a pin receptacle 71 to form an electrical connection between the electronics module 61 and the electrode connection device 63 by means of the feedthrough 65.

(26) Another detail of the electronics module together with a detail of the energy store 62 is shown in FIG. 6. The first pin element 66a, 66b (for example anode and cathode of the battery) is formed on the energy store. The first pin receptacle 67a, 67b is arranged on the electronics module 61. The electronics module 61 is electrically connected to the energy store 62 by means of a straight plug-in connection by inserting the first pin element 66a, 66b into the first pin receptacle 67a, 67b. The connection may be embodied as a redundant connection, for example in that the first pin receptacle 67a, 67b in each case comprises two pin receptacles arranged one above the other (two rings arranged one above the other) (not shown).

(27) The electrical connection between the electronics module 61 and the energy store 62 may be realised with the following technologies: as a cylinder with bore with laser welding (see FIG. 6), as a spring contact in a plug-in connection, and as an angle on the electronics module with resistance welding.

(28) The pins 70 of the feedthrough 65 and the first pin element 66a, 66b point in the same direction (contact direction), which determines the assembly direction for the elements.

(29) An SMD component 72 is arranged on a rear side of the electronics module (see FIGS. 8 and 9).

(30) FIG. 7 shows a block diagram of the implant. The functions of the electronics module are surrounded by the frame 80 and are realised as units/chips on the electronics module and are explained in more detail below.

(31) A radio transceiver 81 is coupled to an antenna 82. The radio transceiver 81 is used for communication with an external device, in particular a programming device. Here, for example, measured values and/or parameters of the implant may be transmitted to the programming device. Changed parameters for the implant may also be received from the programming device.

(32) The electronics module further comprises a control unit 83 (controller). The control unit 83 has a processor, for example a digital signal processor (DSP), a memory such as a RAM (random-access memory) and/or a ROM (read only memory), and a timer. As further functions, a memory access, for example DMA (direct memory access) and/or network functions such as MAC (media access control) may be integrated into the control unit 83.

(33) A measuring unit 86 (sensing unit) is provided as a further component on the electronics module. The measuring unit 86 is configured to take measurements from the heart 91.

(34) A pacemaker unit 85 (pacing unit) is configured to generate stimulation pulses for the heart 91.

(35) The electronics module may optionally comprise a shocking unit 84 (shocking unit) and an HV unit 87 (HV—high voltage), especially if the implant is designed as an ICD. The shocking unit 84 is configured to control the HV unit 87. The HV unit 87 is configured to deliver a shock (defibrillation), for example with a voltage of 700-800 V.

(36) An EMC (electromagnetic compatibility) unit 88 is provided and is designed to minimise or suppress the influence of electromagnetic fields. The electromagnetic fields may include spurious radiation, the field of a shock delivered by the HV unit 87, the field of a stimulation pulse delivered by the pacemaker unit 85, the field of an external shock, the field of an external stimulation, and fields from other external sources (for example a high-frequency measurement). The EMC unit 88 is coupled to the housing 92 of the implant.

(37) The electronics module is coupled to a battery 90. A power unit 89 of the electronics module comprises a switched-mode power supply (SMPS) and is configured for power management.

(38) The functions/units of the electronics module are implemented in various integrated circuits, i.e. chips mounted on the electronics module. The dimensions of the chips result from the complexity of their functions. The higher the complexity, the larger the planar dimensions of the chips. The size of the chips significantly determines the size of the electronics module and also its orientation in the implant (parallel to the energy store). The size of the electronics module is also determined by the number of electrical connections of the chips to one another, of the chips to the non-integrated passive components, and all other connections on the electronics module.

(39) Which therapy functions may be monolithically integrated with each other on one chip by which production process or how many chips the electronics module contains depends on their working voltage range, their data and signal complexity, as well as on their character, i.e. whether they have an analogue, time-continuous or a digital, time-discrete or an analogue-digital, mixed signal behaviour. In principle, all the functions listed above may be monolithically integrated, in particular the digital control functions, the analogue-digital mixed sensing functions for ECG signal amplification and evaluation (ECG—electrocardiogram), the pacing for stimulation pulse generation, the power management for optimal power supply to the implant, and the shocking for voltage generation and control of the defibrillation shock. However, the currently used production processes with minimum structure sizes F=130 nm and F=180 nm result in chips whose dimensions are too large for a vertical arrangement in the implant housing and, moreover, whose data storage capacity (RAM) is too small or must be supplemented with another memory chip to enable all the required therapy and diagnosis functions. For the present implant, some or all of the functions of the electronics module are therefore implemented with chips manufactured with a minimum structure size F≤90 nm, preferably F≤65 nm or F≤55 nm.

(40) One objective is to design the electronics module in such a way that it no longer determines the volume, shape and size of the implant (as in the prior art). To this end, at least one of the following rules is applied: 1. The electronics module is arranged parallel to the front side of the energy store. 2. The length of the electronics module is less than or equal to the length of the electrode connection device. 3. The width of the electronics module is less than or equal to the width of the energy store (or the width of the housing). 4. The length of the energy store is equal to the length of the electrode connection device (maximum volume utilisation). 5. The area of the electronics module corresponds to the area of the front side of the energy store. 6. The volume requirement of the electronics module is less than ¼ of the volume of the energy store (or less than ¼ of the total metal-enveloping volume of the implant).

(41) Applying one or more of these rules results in a strip-shaped, narrow electronics module that is populated with components whose maximum edge length, including their connections, does not exceed the electronics module. Improved optical imaging and lithography processes in semiconductor production are enabling more and more functionality per silicon area. A minimum structure size of the components that is sufficient for production of the implant is F≤90 nm. This allows analogue, digital, analogue-digital mixed, and high-voltage circuits to be increasingly integrated monolithically on one chip. This reduces the number of chips and the number of connections on the electronics module, thus compensating for the smaller available area of the now narrow, strip-shaped module to enable the known functional complexity.

(42) For the production of the integrated circuits on the electronics module, production processes with the following features are selected: At least one chip is produced in a process with a minimum structure size F≤90 nm. Alternatively, at least one chip is produced in a process with a minimum structure size F≤65 nm. Alternatively, at least one chip is produced in a process with minimum structure size F≤65 nm, to which a voltage of ≥10 V with respect to its substrate may be connected simultaneously. Alternatively, at least one chip is produced in a process with a minimum structure size F≤65 nm, to which a voltage of ≥10 V with respect to its substrate may be connected simultaneously and the SRAM (static random-access memory, static RAM) memory functions of the chip has a capacity of ≥3 megabits.

(43) The electronics module with the form factor described here is suitable for mounting in the cross-section of the flat implant, in particular between the energy store and the electrode connection device. This assembly location results in further features of the electronics module that may be realised individually or in any combination with each other: perpendicular connections for wired components on the top side and/or underside of the electronics module, bores, onto or through which connections of components, for example battery connections and/or header connections, may be plugged, and a bore fit to accommodate cutting sleeves and/or clamping sleeves.

(44) Sawed, straight edges also enable optimal manufacture of the electronics module in panelised form in a standard packaging technique for Ball Grid Array Packages (μBGAs). In a μBGA, the chips are assembled on a printed circuit board substrate (PCB substrate), bonded, and covered with a molding compound in a transfer overmolding process. Solder balls are applied to the back of the substrate for SMD assembly. The packaging takes place in the panelised state. The printed circuit board substrate always has a uniform panel size for all chip sizes, which only depends on the molding tool of the transfer molding machine.

(45) Depending on the chip size, more or fewer chips fit on the panel and are then sawn out of the panel in their final package size after potting and equipping with solder balls.

(46) In one embodiment, there are three square potting areas, each with an edge length of 56 mm, on a 205 mm×70 mm panel, into which the chips are assembled and wire bonded (see FIGS. 10A and 10B). The application of this μBGA packaging process to the electronics module leads to further characteristics and extensions of the packaging process, which are shown in FIGS. 10A to 10E. After transfer molding, the holes or fits of the cutting sleeves and/or clamping sleeves are drilled (see FIG. 10C). The potting not only serves to cover the chips, it is also part of the mechanical stability of the electronics module and in particular of the resulting plug-in connection. Instead of solder balls, the panel is populated with the SMD components of the electronics modules in panelised form (see FIG. 10D). The edge lengths of the electronics module fulfil an integer divider ratio of the potting surface edges of the panel minus the sawing losses. The components of the electronics module may be provided as ASICs (application-specific integrated circuits).

(47) Some of the production steps are summarised below: FIG. 10A: ASICs 101 in panelised form are assembled and bonded on a first side (front side) of the panel 100. FIG. 10B: transfer overmolding of the assembled ASICs 101 with a potting agent 102. FIG. 10C: drilling the holes 103 for a connection of the energy store. FIG. 10D: population of a second side (rear side) of the panel 100 with SMD components 104. FIG. 10E: sawing out the finished electronics modules. FIGS. 11 to 17 show the individual steps for assembling an electrode connection device (header) on an implant. The steps are explained in more detail below.

(48) FIG. 11 shows an assembly 1 (also referred to as a header core) with a first receiving means 2 for a male electrode connector and a second receiving means 13 for a further male electrode connector. The first receiving means 2 has a front opening 6, through which the male electrode connector may be inserted. The first receiving means 2 has a first portion 3, a second portion 4 and a third portion 5. The diameter of the first portion 3 is larger than the diameter of the second portion 4. The diameter of the second portion 4 is in turn larger than the diameter of the third portion 5. In other words, the first receiving means 2 is gradually tapered from the front opening 6 towards the end.

(49) A first connection element is formed between the first portion 3 and the second portion 4 (i.e. in a front region of the first receiving means 2). A second connection element 8 is formed between the second portion 4 and the third portion 5 (in a rear region of the first receiving means 2). Both the first connection element 7 and the second connection element 8 have at least two flat side faces. This enables easy gripping of the assembly 1 during an assembly and enables automation of the assembly steps. In the embodiment shown, the first connection element 7 and the second connection element 8 are substantially cuboid-shaped. The second connection element 8 has a bevelled edge 17, which serves to save material and to observe the flow direction of the epoxy resin. A recess 12a is formed in the plastics material coating on a rear side of the first connection element 7. A rear opening 12b is formed on a rear side of the second connection element 8.

(50) The assembly is partially surrounded by a plastics material 11. In the embodiment shown, the assembly is partially overmolded with polysulfone. Recesses for a first contact face 9 and a second contact face 10 are formed in the plastics material 11. The first and second contact faces are formed as circular faces. A guide 16 is formed adjacent to each of the first and second contact faces 9, 10. The guide 16 serves to receive a connection element (for example a wiring strip). The guides on the contact faces prevent connection elements from different contact faces from touching each other.

(51) The second receiving means 13 is constructed analogously to the first receiving means 2. For reasons of clarity, the components of the second receiving means (an opening, the three step-shaped tapering portions and the two connection elements) are not provided with reference signs. The second receiving means also has two contact faces (third contact face 14 and fourth contact face 15) for connections. Guides are again formed adjacently to the contact faces.

(52) A positioning means 18b is formed at one end of the second receiving means and is embodied as a pin with a pointed end. When assembling the assembly 1 on a housing 29 (see FIG. 15), the pointed end of the positioning means 18b may be inserted into a receptacle of the housing in order to facilitate the precisely fitting arrangement of the assembly on the housing. However, the assembly may also be embodied without positioning means 18b.

(53) Positioning pins 18a are formed on an underside of the assembly (see FIG. 12). The positioning pins may be arranged in associated receptacles when the assembly is arranged on the housing of the implant. In the embodiment shown, two positioning pins are shown, but other numbers of positioning pins are possible.

(54) The first receiving means 2 and the second receiving means 13 each have a spring sleeve and a male connector receptacle. The first receiving means 2 and the second receiving means 13 may be designed as IS-1 connectors.

(55) A spring element 20 is arranged in the first receiving means 2 and fastened there (left side of FIG. 13). The recess 12a in the plastics material is used to weld the spring element 20 arranged inside the first receiving means 2 into the first connection element 7 by means of resistance welding. Similarly, another spring element is arranged and fastened in the second receiving means 13 (not shown). The openings of the assembly 1 are then closed and sealed with potting aids 21, 22, 23 (right side of FIG. 13).

(56) A further assembly step is shown in FIG. 14. A wire strip 24 is fastened (for example welded) to the third contact face 14. At its rear end, the wire strip 24 has a wire strip connection 25, which is connectable to a pin contact of a feedthrough 30 (see FIG. 4) and may, for example, be plugged onto the pin contact. Further wire strips are connected to the other contact faces 9, 10, 15.

(57) An antenna 26 is attached to the assembly 1. The antenna 26 partially surrounds the first portion 3 of the first receiving means 2 and is clipped thereto. In a region between the first connection element 7 and the second connection element 8, the antenna 26 has a U-shaped portion 27. This forms a grip recess that may be used, for example, with an automated gripper to hold and transport the assembly. An antenna connection 28 is formed at a rear end of the antenna for connection to the feedthrough 30.

(58) The assembly with the wire strips and the antenna is then placed in a mold (for example a silicone mold) (not shown). The wire strip connections and the antenna connection 28 are placed on associated pins of the feedthrough 30 and are connected to the pins (for example welded). The mold is closed and filled with a synthetic resin 31 (for example epoxy resin). This forms the electrode connection device (see FIG. 16).

(59) The potting aids 21, 22, 23 are removed and any excess resin on the outer surfaces is removed, for example by grinding and/or polishing. The implant with the electrode connection device is now completely assembled (FIG. 17).

(60) FIG. 18 shows another embodiment of the implant. The electrode connection device 53 is attached to a cover 121. The energy store 62 is received in a housing 120. The housing 120 may be provided as a deep-drawn molded part. The cover 121 is welded to the housing 120 along a circumferential weld seam 122 to close the housing 120. A support frame 69 is arranged on the energy store. The support frame 69 receives the electronics module. The electrode connection device 53 may be formed, for example, according to the embodiment shown in FIGS. 11 to 17. The feedthrough 65 with the pins 70 is welded into the cover 121.

(61) The embodiments of the implant and methods disclosed herein may have the following advantages:

(62) The internal structure of the electronic implant is significantly simplified, thus reducing production costs. Similarly, the number and complexity of the required production processes decreases, thus favouring the scalability of production (for example simplified transfer to other locations, reduced training needs for employees, reduced requirements for the required manufacturing environment and accompanying engineering). Furthermore, reworking becomes possible or simplified when detachable joining techniques are used.

(63) With the form factor of the electronics module, the implant may be made smaller or the volume gained may be used to increase battery capacity and thus extend the service life of the implant. The production of the electronics module in μBGA technology enables an increase in the usefulness on the panel and an associated production cost saving. The vertical assembly of the electronics module (parallel to the front side of the energy store) enables electrical connections without angles and thus a simpler, more economical construction of the implant, optimised for automatic manufacturing in one axis.

(64) The features disclosed in the description, the claims and the figures may be relevant for the realisation of embodiments both individually and in any combination with each other.

(65) It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings of the disclosure. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. Additionally, the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points.