U.S. patent application number 15/439061 was filed with the patent office on 2017-06-08 for portable power charging of implantable medical devices.
The applicant listed for this patent is Werner Meskens. Invention is credited to Werner Meskens.
Application Number | 20170157408 15/439061 |
Document ID | / |
Family ID | 46200128 |
Filed Date | 2017-06-08 |
United States Patent
Application |
20170157408 |
Kind Code |
A1 |
Meskens; Werner |
June 8, 2017 |
PORTABLE POWER CHARGING OF IMPLANTABLE MEDICAL DEVICES
Abstract
An implantable medical device, comprising an implantable
component having a rechargeable power supply and an external
wireless charger. The wireless charger has a rechargeable power
supply, and an inductive coil configured to transcutaneously
transfer power from the charger power supply to the implantable
power supply, and configured to detect and receive, via the
inductive coil, power from an auxiliary charger for recharging of
the charger power supply.
Inventors: |
Meskens; Werner; (Opwijk,
BE) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Meskens; Werner |
Opwijk |
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BE |
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|
Family ID: |
46200128 |
Appl. No.: |
15/439061 |
Filed: |
February 22, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14838666 |
Aug 28, 2015 |
9597522 |
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15439061 |
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12965415 |
Dec 10, 2010 |
9132276 |
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14838666 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04R 2225/67 20130101;
H02J 7/025 20130101; H02J 7/00034 20200101; H04R 2225/31 20130101;
H02J 50/40 20160201; A61N 1/37217 20130101; A61N 1/3787 20130101;
A61N 1/37223 20130101; H02J 50/10 20160201; A61N 1/36038
20170801 |
International
Class: |
A61N 1/378 20060101
A61N001/378; H02J 50/10 20060101 H02J050/10; H02J 7/02 20060101
H02J007/02; A61N 1/372 20060101 A61N001/372; A61N 1/36 20060101
A61N001/36 |
Claims
1. A sound processor, comprising: a battery; an inductive coil; and
a circuit configured to route power from the battery to the
inductive coil for transcutaneous transfer of the power to an
implantable component, and to route power received via the
inductive coil from an auxiliary power source to the battery to
recharge the battery, wherein the sound processor is configured to
detect the presence of an inductive field generated by the
auxiliary power source, and, in response to the detection,
automatically route power from the inductive coil to the
battery.
2. The sound processor of claim 1, wherein the circuit comprises a
routing system, driver, and a battery recharger, and wherein the
routing system is connected among the driver, the inductive coil,
and the battery recharger.
3. The sound processor of claim 1, wherein the sound processor is
further configured to transcutaneously transmit data from the sound
processor to the implantable component via the inductive coil.
4. The sound processor of claim 1, further comprising a power
detector connected to the inductive coil, wherein the power
detector is configured to detect the presence of the inductive
field generated by the auxiliary power source.
5. The sound processor of claim 1, further comprising a controller
configured to control the circuit so as to enable routing of power
from the battery to the inductive coil only during selected time
periods.
6. A sound processor, comprising: an inductive coil; a battery; and
a circuit connecting the battery to the inductive coil, wherein the
circuit is configured to drive the inductive coil with power
received from the battery, and to route power received at the
inductive coil to the battery.
7. The sound processor of claim 6, wherein the circuit comprises a
routing system, a driver, and a battery recharger, wherein the
routing system is connected among the driver, the inductive coil,
and the battery recharger.
8. The sound processor of claim 6, wherein the inductive coil is
further configured to transcutaneously transmit data from the sound
processor to an implantable component.
9. The sound processor of claim 6, further comprising an external
accessory, wherein the inductive coil is configured to form a
bidirectional data link with the external accessory.
10. The sound processor of claim 6, wherein the circuit enables the
inductive coil to transcutaneously transfer power from the battery
to an implantable component and to transfer power received from an
auxiliary power source to the battery.
11. The sound processor of claim 10, wherein the circuit includes a
controller configured to enable the transcutaneously transfer of
power from the battery to the implantable component via the
inductive coil for a first time period, and to disable the
transcutaneously transfer of power from the battery to the
implantable component via the inductive coil for a second time
period.
12. The sound processor of claim 11, wherein the circuit is
configured to monitor for the presence of the auxiliary power
source during the second time period.
13. The sound processor of claim 12, wherein when the circuit
detects the presence of the auxiliary power source, the inductive
coil is configured to receive power from the auxiliary power source
and the circuit is configured to enable the transfer of power
received from the auxiliary power source to the battery.
14. The sound processor of claim 13, wherein before enabling the
transfer of power received from the auxiliary power source to the
battery, the circuit is configured to perform a check to determine
if the battery can accept additional power.
15. The sound processor of claim 6, wherein the sound processor is
a Behind-the-Ear (BTE) device.
16. The sound processor of claim 6, wherein the sound processor is
a body worn device.
17. A sound processor, comprising: a battery; an inductive coil;
and a circuit connected between the battery and the inductive coil,
wherein the circuit includes a controller configured to enable
transcutaneous transfer of power from the battery to an implantable
component via the inductive coil during a first time period, and to
disable the transcutaneous transfer of power from the battery to
the implantable component via the inductive coil during a second
time period.
18. The sound processor of claim 17, wherein the circuit is
configured to drive the inductive coil so as to transmit the power
to the implantable component, and wherein the circuit is configured
to detect and receive, via the inductive coil, power from an
auxiliary power source for recharging of the battery.
19. The sound processor of claim 18, wherein the circuit comprises
a power detector connected to the inductive coil, wherein the power
detector is configured to detect the presence of an inductive field
generated by the auxiliary power source.
20. The sound processor of claim 18, wherein the power detector is
configured to periodically determine whether the auxiliary power
source is capable of supplying power sufficient to recharge the
battery.
21. The sound processor of claim 18, wherein in response to
detecting the presence of the inductive field generated by the
auxiliary power source, the circuit is automatically arranged to
route power from the inductive coil to the battery.
22. The sound processor of claim 18, wherein when the circuit
detects the presence of the auxiliary power source, the inductive
coil is configured to receive power from the auxiliary power source
and the circuit is configured to enable the transfer of power
received from the auxiliary power source to the battery.
23. The sound processor of claim 22, wherein before enabling the
transfer of power received from the auxiliary power source to the
battery, the circuit is configured to perform a check to determine
if the battery can accept additional power.
24. The sound processor of claim 17, wherein the circuit is further
configured to transcutaneously transfer of data from the sound
processor to the implantable component via the inductive coil
during the second time period.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/838,666, filed Aug. 28, 2015, which in turn
is a continuation of U.S. patent application Ser. No. 12/965,415,
filed Dec. 10, 2010, now U.S. Pat. No. 9,132,275, the entire
contents of which is incorporated herein by reference.
BACKGROUND
Field of the Invention
[0002] The present invention relates generally to implantable
medical devices, and more particularly, to portable power charging
of implantable medical devices.
Related Art
[0003] Medical devices having one or more implantable components,
generally referred to herein as implantable medical devices,
provide a wide range of therapeutic benefits to recipients. Certain
implantable medical devices, sometimes referred to as active
implantable medical devices (AIMDs), include an implantable power
supply that provides power to one or more implantable components.
AIMDS include, but are not limited to, certain implantable hearing
prostheses, neural stimulators, drug pumps and cardiac devices.
[0004] One type of hearing prosthesis that is widely used is the
partially implantable cochlear implant. Traditionally, partially
implantable cochlear implants consist of an external speech
processor unit and an implanted receiver/stimulator unit. The
external speech processor unit is worn on the body of the user,
such as a behind-the-ear (BTE) device. BTE devices are generally
configured to receive sound with a sound input element, such as a
microphone, and to convert the received sound into an electrically
coded data signal that is transcutaneously transferred to the
implanted receiver/stimulator unit. The BTE device is also
generally configured to transcutaneoulsy transfer power to the
implanted receiver and stimulator unit. More particularly, the
power and data are transcutaneously transferred via a magnetic
induction link established in a reactive near-field between an
external coil closely coupled to an implanted coil.
[0005] Traditionally, the operating power for the BTE device and
implanted components is provided by batteries, such as Zn-Air
batteries, housed in the device. The closely coupled coils include
an external coil coupled to the BTE device which is configured to
be placed in close proximity to the coil of the implanted
component. However, due to improvements in power storage
technology, it has become more common for implantable hearing
prosthesis and other AIMDs to include an implantable power supply
that is sufficient to allow for periods of operation without access
to an external power source. Such implantable power storage has
enabled certain devices, in particular hearing prostheses, to
become totally or fully implantable.
[0006] In addition to an implantable power supply, totally
implantable hearing prostheses also have one or more components
that were traditionally external to the recipient, such as the
sound processor, implantable in the recipient. Accordingly, totally
implantable prostheses to operate independently (that is, without
an external device) for periods of time. It would be appreciated
that, as used herein, totally or fully implantable hearing
prosthesis may include external devices such as microphones, remote
controls, etc.
[0007] Various implantable power storage systems have been
proposed. However, in all implantable systems it remains necessary
to transfer power from an external power supply to recharge the
implanted power storage system. Devices continue to use the closely
coupled external/internal coils to transfer the power, although the
headpiece coil is not continuously required for regular operation.
Data transfer may occur using alternative wireless links, for
example short range EM (electro-magnetic) links (e.g. 400 MHz) or
MI (magnetic induction) links (e.g. 10.7 MHz).
SUMMARY
[0008] In one aspect of the present invention, a wireless charger
of an implantable medical system is provided. The wireless charger
comprises a charger power supply; an inductive coil; and a routing
system configured to route power provided by the charger power
supply to the inductive coil for transcutaneous transfer of the
power to an implantable component, and to route power received via
the inductive coil from an auxiliary charger to the charger power
supply for recharging of the charger power supply.
[0009] In another aspect of the present invention, an implantable
medical system is provided. The implantable medical system
comprises an auxiliary charger; an implantable component including
a implantable power supply; and a wireless charger comprising: a
charger power supply, and an inductive coil connected to the
charger power supply via a circuit enabling the inductive coil to
transcutaneously transfer power from the charger power supply to
the implantable power supply and to transfer power received from
the auxiliary charger to the charger power supply.
[0010] In a still other aspect of the present invention, an
implantable medical system is provided. The implantable medical
system comprises an external auxiliary charger; and an external
wireless charger including: a charger power supply, an inductive
coil, and a circuit connected between the charger power supply and
the inductive coil configured to drive the inductive coil so as to
transmit power an implantable power supply, and configured to
detect and receive, via the inductive coil, power from the
auxiliary charger for recharging of the charger power supply.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Embodiments of the present invention are described below
with reference to the attached drawings, in which:
[0012] FIG. 1A is a schematic diagram of a cochlear implant, in
accordance with embodiments of the present invention;
[0013] FIG. 1B is a schematic diagram illustrating exemplary
external accessories that may be implemented in accordance with
embodiments of the present invention;
[0014] FIG. 2 is a schematic block diagram of a wireless charger,
in accordance with embodiments of the present invention;
[0015] FIG. 3 is a schematic diagram illustrating one
implementation of an auxiliary charger, in accordance with
embodiments of the present invention;
[0016] FIG. 4 is a schematic diagram illustrating of a cochlear
implant system, in accordance with embodiments of the present
invention;
[0017] FIG. 5 is a schematic diagram of a wireless charger having
the coil integrated in its housing, in accordance with embodiments
of the present invention;
[0018] FIG. 6 is a block diagram of an alternative implementation
of a wireless charger, in accordance with embodiments of the
present invention;
[0019] FIG. 7 is a flow chart of a charging process for a wireless
charger, in accordance with embodiments of the present
invention;
[0020] FIG. 8 is a timing diagram corresponding to the method
illustrated in FIG. 7;
[0021] FIG. 9A is a perspective view of a wireless charger, in
accordance with embodiments of the present invention; and
[0022] FIG. 9B is a perspective view of a wireless charger, in
accordance with embodiments of the present invention.
DETAILED DESCRIPTION
[0023] Aspects of the present invention are generally directed to
an implantable medical device or system having an implantable power
supply that receives power from wireless charger worn by a
recipient of the device. The wireless charger also includes a
rechargeable power supply, and is configured to transcutaneously
transfer power to the implantable power supply. The wireless
charger is also configured to receive power from an auxiliary
charger. In certain embodiments, the wireless charger includes one
inductive coil that is used to both receive and transmit power.
[0024] Embodiments of the present invention will be described with
reference to a particular illustrative implantable medical system,
namely a cochlear implant system, commonly referred to as a
cochlear prosthesis or simply cochlear implant. It would be
appreciated that embodiments of the present invention may be
implemented in other medical systems utilizing or requiring
periodic transfer of power via an indicative link. Exemplary
devices include, but are not limited to, neural or muscle
stimulators, drug pumps, cardiac devices, and other hearing
prosthesis such as hybrid electrical/acoustic systems, acoustic
hearing aid systems, middle ear stimulators, or fully external
hearing systems, etc.
[0025] FIG. 1A is a schematic diagram of a cochlear implant 100 in
accordance with embodiments of the present invention. As shown,
cochlear implant 100 comprises an implantable component 104
positioned below a recipient's skin and other tissue (not shown),
and external component(s) 102. In the embodiment of FIG. 1A,
external component(s) 102 comprise a wireless charger 110, and an
external accessory 106. Further details of wireless charger 110 and
external accessory 106 are provided below.
[0026] As shown, wireless charger 110 includes a radio frequency
(RF) headpiece coil 112. Headpiece coil 112 is configured to be
inductively coupled to RF coil 116 in implantable component 104 via
inductive link 132. Implantable coil 116 is connected to a
transceiver unit 128.
[0027] As shown, implantable component 104 also includes an
implantable power supply, shown as a rechargeable battery unit 118,
a stimulator unit 120, an intracochlear electrode assembly 122 and
one or more supplementary extracochlear ground electrode(s) 124. In
the embodiments of FIG. 1A, transceiver 128, battery unit 118 and
stimulator unit 120 are positioned in a hermetically sealed housing
130. Implantable component 104 also includes an electronics module
114 that may comprise, for example, a sound processor, memory,
controller, etc.
[0028] In the embodiments of FIG. 1A, a separate implantable
microphone 126 is also provided. Microphone 126 may be electrically
coupled to one or more components in housing 130 via a cable/lead,
or via a wireless link 144.
[0029] In embodiments of the present invention, wireless charger
110 includes a rechargeable power supply, sometimes referred to
herein as charger power supply or battery system 134. In certain
embodiments, battery system 134 comprises one or more rechargeable
batteries 134. Although for ease of discussion the term battery
system is used to refer to the power supply within the charger, it
would be appreciated that any rechargeable power source that is
able is sufficiently small and is able to fulfill the power
requirements of the device may be used. For example, in certain
embodiments, a Li-ion or Li-polymer battery unit is used. As is
known in the art, such batteries may be shaped to fit perfectly in
housings having different geometries. In other embodiments, nickel
cadmium, metal hydride, a supercapacitor based system or even
energy stored in a spring wound up by a clockwork mechanism may
used.
[0030] Wireless charger 110 is configured to provide power from
battery system 134 to implantable battery unit 118. The power is
inductively transferred via link 132. As described further below,
battery system 134 of wireless charger 110 is recharged by
receiving power from an auxiliary charger via headpiece coil
112.
[0031] As previously noted, one or more external accessories 106
may also be worn by the recipient and may communicate with
implantable component 104. Specifically, an external accessory 106
is a device that communicates with implantable component 104 via a
low-power wireless data link 140. In certain embodiments, an
external accessory 106 includes a microphone and/or sound
processor. Exemplary external accessories 106 are schematically
shown in FIG. 1B as a mini-BTE (106A), micro-BTE (106B), in-the-ear
(ITE) device (106C), an in-the canal (ITC) device (106D), open-fit
or over-the-ear device (OTE) (not shown), or other device.
Exemplary data links are described in US Patent Application
US2008/0300658, the contents of which are hereby incorporated by
reference herein. FIG. 9A is a perspective view of a wireless
charger 910A that is a BTE device. Similarly, FIG. 9B is a
perspective view of a body worn charger 910B.
[0032] FIG. 1A illustrates embodiments of the present invention in
which wireless charger 110 and external accessory 106 are separate
components. It would be appreciated that in embodiments of the
present invention, external accessory 106 and wireless charger 110
may comprise the same component. For example, in embodiments of the
present invention, a BTE device may operate as the wireless charger
and may include components of an external accessory, such as a
sound processor, microphone etc.
[0033] FIG. 2 is a schematic block diagram of an implementation of
a wireless charger 110 of FIG. 1A. As shown, charger 110 includes a
power supply, such as rechargeable battery system 134. To transfer
power to implantable component 104 (FIG. 1), power from battery
system 134 is provided to DC/AC converter 240, that then provides
an AC waveform to driver 242. The AC waveform may be modulated for
transfer of data to implantable component 104 via link 132 (FIG.
1), or if spreading of the frequency spectrum is desired to reduce
dense spectral power components (EMC). Driver 242 amplifies the
waveform to a suitable signal level for power transfer to
implantable component 104. The amplified signal from driver 242 is
provided to routing system 244, which controls the flow of power to
and from coil 50. Specifically, routing system 244 is configured to
function as a coupler/splitter for signals received from driver 240
and coil 112. Routing system 244 may include components for driving
coil 112 to transmit the power signals to implantable component
104.
[0034] As previously noted, coil 112 in wireless charger 110 is
used to inductively transfer power to implantable component 104,
and to receive power from auxiliary charger 350. Using the same
coil for both transmission and receipt of power simplifies the
manufacturing process and enhances friendliness and simplicity of
use. Accordingly, wireless charger 110 receives power from an
auxiliary charger via coil 112 and the received power is routed
from the coil to battery recharger 246 and battery system 134.
[0035] FIG. 3 is a perspective view of one implementation of an
auxiliary charger 350 in accordance with embodiments of the present
invention. As shown, auxiliary charger 350 comprises a base 352 on
which an array of coils 354A, 354B, and 354C is positioned.
Attached to base 356 is a plug 356 for connecting auxiliary charger
350 to a 12V power source, DC power supply (e.g., in a car), or
other power sources. In operation, when wireless charger 110 is in
proximity to auxiliary charger 350, one of the coils 354A, 354B, or
354C is inductively coupled to coil 112. By having an array of
coils 354A-C, rather than only one coil, the system makes it easier
for a recipient to couple chargers 110 and 350. Specifically, the
array of coils increases the likelihood that the recipient will be
able to position the wireless charger 110 appropriately so that an
inductive link is formed between coil 112 and a coil 354. When
wireless charger 110 is fully charged, auxiliary charger 350 and
the wireless charger may be separated.
[0036] It would be appreciated that auxiliary charger 350 may have
a variety of arrangements. For example, auxiliary charger 350 may
be a charging pad, a cradle, a docking station, or any suitable
arrangement. Auxiliary charger 350 may also be adapted to charge
other devices, for example any externally worn microphone or remote
control units.
[0037] FIG. 4 is a schematic diagram illustrating wireless links
between auxiliary charger 350, wireless charger 110 and implantable
component 104. As would be appreciated, the links shown in FIG. 4
are merely illustrative and additional links could be provided.
Alternatively, all of the links shown in FIG. 4 are not necessary
and one or more links may be omitted in different
configurations.
[0038] As shown in FIG. 4, a wireless power link 464 is provided
between a coil 354 (FIG. 3) in auxiliary charger 350, and headpiece
coil 112. Additionally, a feedback link 462 is provided to transmit
data information between auxiliary charger 352 and wireless charger
110. For example, link 462 may used by wireless charger 110 to
instruct auxiliary charger 350 to adjust link 464, or to adjust
other characteristics of the auxiliary charger.
[0039] Also as shown in FIG. 4, link 132 is provided between
implantable coil 116 and headpiece coil 112 to transmit power from
wireless charger 110 to implantable component 104. In certain
embodiments, a bidirectional data link 466 may also be provided
between coils 112 and 116 to transmit data to or from implantable
component 104.
[0040] As noted above, in embodiments of the present invention a
wireless charger also operates as an external accessory. That is,
the wireless charger includes components of an external accessory,
such as a sound processor, microphone, control electronics, etc. In
such embodiments, an additional data link may be provided between
the wireless charger and the implantable component. However, in
certain embodiments, the wireless charger is a simple charging
arrangement that does not otherwise interact with the implantable
component.
[0041] FIG. 5 is a schematic diagram of an alternative cochlear
implant 500 in accordance with embodiments of the present
invention. As shown, cochlear implant 500 comprises an implantable
component 504 that is substantially the same as implantable
component 104 of FIG. 1. Cochlear implant 500 further comprises a
wireless charger 510. As shown, wireless charger 510 has a coil 512
wireless charger in its housing 514.
[0042] Also shown in FIG. 5 are exemplary magnetic flux lines 520
generated by coil. As shown, magnetic flux lines 520 pass through
implantable coil 516, thereby inductively coupling coil 512 to coil
516.
[0043] As noted above, FIG. 3 is a schematic block diagram of one
embodiment of wireless charger 110 of FIG. 1. FIG. 6 is a schematic
block diagram of an alternative wireless charger 610 having a
controller 670 to manage recharging and communications of the
charger. Charger 610 has components that are substantially the same
as described above with reference to FIG. 3, including batteries
634, DC/AC converter 640, driver 642, routing system 644, and
battery recharger 646. However, as shown in FIG. 7, wireless
charger 610 includes several components, namely power detector 672
and controller 670, that are not found in wireless charger 110 of
FIG. 3. As described below, the power emanating from wireless
charger unit 610 is provided to the implantable component 104. The
auxiliary power emanating from auxiliary charger 350 (FIG. 3) is
provided to wireless charger unit 610 to charge the batteries
therein or thereon.
[0044] For ease of description, the operation of controller 670
will described with reference to the control process 700 of FIG.
7.
[0045] Control process begins at block 704 after the wireless
charger is powered ON at block 702. More particularly, at block 704
controller 670 of wireless charger 610 initially operates the
primary power link for a time duration T1. The primary power link
is the link between external coil 612 of wireless charger 610 and
the implantable coil. At block 706, controller 670 disables primary
power link for a time duration T2, and monitors for the presence of
the auxiliary charger. In certain embodiments, T2 is preferably
relatively short when compared to T1. Referring to the embodiments
of FIG. 6, the presence of the auxiliary charger may be detected by
power detector 672. It should be noted that in certain embodiments
the primary power link is disabled for a short time at block 706 to
allow detection (presence or absence) of auxiliary power sources or
implantable components.
[0046] At block 708, controller 670 performs a check to determine
if the auxiliary charger is detected. If the auxiliary charger is
not detected, control process 700 returns to block 704 where
controller 670 again enables primary power link for T1. This
process continues until the auxiliary charger has been
detected.
[0047] When the auxiliary power source is detected, control process
700 continues to block 710 where controller 670 performs a check of
whether the battery is fully charged. If the battery is not fully
charged, controller 670 activates the auxiliary link (that is, the
link between the wireless charger and the auxiliary charger), and
the battery(ies) of the wireless charger are recharged at block
712. If, at block 710, it is determined that the battery(ies) are
fully charged, control process 700 returns to block 704. It would
be appreciated that control process 700 of FIG. 7 is one
implementation, and other methods for managing wireless charger and
the dual purpose coil and associated systems may be implemented in
alternative embodiments of the present invention
[0048] FIG. 8 is a timing diagram schematically illustrating how
certain components of wireless charger 610 are operated during
control process 700.
[0049] Specifically, FIG. 8 shows the output 680A of power detector
672, the input 680B of DC/AC converter 640, and the output 680C of
battery recharger 646 during times T1 and T2. As shown, when power
is being provided via the primary link, input 680B of DC/AC
converter 640 is high, while output 680C of battery recharger 646
is low (that is, battery recharger 646 is disabled). As noted
above, controller 670 monitors for the presence of the auxiliary
charger during times T2.
[0050] In one embodiment shown in FIG. 4 a wireless backlink 466
from the implantable component 104 to the wireless charger 110, for
example similar to the telemetry systems known for cochlear
implants, provides the type of implantable component and status
information on the state of the implanted rechargeable battery to
the recharger during its charging and discharging cycle. The
wireless back link is optional and could be operating over the same
or a different RF frequency channel. In case the RF frequency
channel is shared a TDMA scheme becomes necessary. In both cases
the system requires additional communication blocks. As an
alternative to TDMA load modulation could be applied by switching
on and off a small load resistance on the BTE charger. This would
result in a voltage variation over the auxiliary coil such as in
amplitude modulation.
[0051] All references referred to in the specification are hereby
incorporated by reference into this disclosure. Many variations and
additions are possible within the general inventive scope.
* * * * *