Abstract: A design for an implantable medical device (IMD) is disclosed in which a charging coil and a short-range RF antenna in the IMD's header are physically integrated, and in which the short-range RF antenna includes intentional coupling to the charging coil. A pick-up is capacitively coupled to the charging coil in the header, such as by wrapping the pick-up at least partially around the turns of the charging coil. The charging coil is used to receive power via a magnetic inductive link at a first (preferably lower) frequency, while the combined charging coil and pick-up—together acting as the short-range RF antenna—receive and transmit short-range RF data (e.g., Bluetooth) via a short-range RF data link at a second (preferably higher) frequency. Resonance of the charging coil and short-range RF antenna can be independently tuned, and circuitry can prevent interference between them.

Abstract: A design for an implantable medical device (IMD) is disclosed in which a charging coil and a short-range RF antenna in the IMD's header are physically integrated, and in which the short-range RF antenna includes intentional coupling to the charging coil. A pick-up is capacitively coupled to the charging coil in the header, such as by wrapping the pick-up at least partially around the turns of the charging coil. The charging coil is used to receive power via a magnetic inductive link at a first (preferably lower) frequency, while the combined charging coil and pick-up-together acting as the short-range RF antenna-receive and transmit short-range RF data (e.g., Bluetooth) via a short-range RF data link at a second (preferably higher) frequency. Resonance of the charging coil and short-range RF antenna can be independently tuned, and circuitry can prevent interference between them.

Abstract: A charging system for an Implantable Medical Device (IMD) is disclosed having a charging coil and one or more sense coils. The charging coil and one or more sense coils are preferably housed in a charging coil assembly coupled to an electronics module by a cable. The charging coil is preferably a wire winding, while the one or more sense coils are concentric with the charging coil and preferably formed in one or more traces of a circuit board. One or more voltages induced on the one or more sense coils can be used to determine the resonant frequency of the charging coil/IMD coupled system. The determined resonant frequency can then be used to determine the position of the charging coil relative to the IMD. The magnetic field produced from the charging coil may also be driven at the resonant frequency to optimize power transfer to the IMD.

Abstract: A design for an implantable medical device (IMD) is disclosed in which a charging coil and a short-range RF antenna in the IMD's header are physically integrated, and in which the short-range RF antenna includes intentional coupling to the charging coil. A pick-up is capacitively coupled to the charging coil in the header, such as by wrapping the pick-up at least partially around the turns of the charging coil. The charging coil is used to receive power via a magnetic inductive link at a first (preferably lower) frequency, while the combined charging coil and pick-up—together acting as the short-range RF antenna—receive and transmit short-range RF data (e.g., Bluetooth) via a short-range RF data link at a second (preferably higher) frequency. Resonance of the charging coil and short-range RF antenna can be independently tuned, and circuitry can prevent interference between them.

Abstract: A design for an implantable medical device (IMD) is disclosed in which a charging coil and a short-range RF antenna in the IMD's header are physically integrated, and in which the short-range RF antenna includes intentional coupling to the charging coil. A pick-up is capacitively coupled to the charging coil in the header, such as by wrapping the pick-up at least partially around the turns of the charging coil. The charging coil is used to receive power via a magnetic inductive link at a first (preferably lower) frequency, while the combined charging coil and pick-up—together acting as the short-range RF antenna—receive and transmit short-range RF data (e.g., Bluetooth) via a short-range RF data link at a second (preferably higher) frequency. Resonance of the charging coil and short-range RF antenna can be independently tuned, and circuitry can prevent interference between them.

Abstract: Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Abstract: Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Abstract: A design for an implantable medical device (IMD) is disclosed in which a charging coil and a short-range RF antenna in the IMD's header are physically integrated, and in which the short-range RF antenna includes intentional coupling to the charging coil. A pick-up is capacitively coupled to the charging coil in the header, such as by wrapping the pick-up at least partially around the turns of the charging coil. The charging coil is used to receive power via a magnetic inductive link at a first (preferably lower) frequency, while the combined charging coil and pick-up—together acting as the short-range RF antenna—receive and transmit short-range RF data (e.g., Bluetooth) via a short-range RF data link at a second (preferably higher) frequency. Resonance of the charging coil and short-range RF antenna can be independently tuned, and circuitry can prevent interference between them.

Abstract: Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Abstract: A charging system for an Implantable Medical Device (IMD) is disclosed having a charging coil and one or more sense coils. The charging coil and one or more sense coils are preferably housed in a charging coil assembly coupled to an electronics module by a cable. The charging coil is preferably a wire winding, while the one or more sense coils are concentric with the charging coil and preferably formed in one or more traces of a circuit board. One or more voltages induced on the one or more sense coils can be used to determine the resonant frequency of the charging coil/IMD coupled system. The determined resonant frequency can then be used to determine the position of the charging coil relative to the IMD. The magnetic field produced from the charging coil may also be driven at the resonant frequency to optimize power transfer to the IMD.

Abstract: Receiver and digital demodulation circuitry for an external controller for communicating with an implantable medical device (IMD) is disclosed. A Digital Signal Processor (DSP) is used to sample received analog data transmitted from the IMD at a lower rate than would otherwise be required for the frequency components in the transmitted data by the Nyquist sampling criteria. To allow for this reduced sampling rate, the incoming data is shifted to a lower intermediate frequency using a switching circuit. The switching circuit receives a clock signal, which is preferably but not necessarily the same clock signal used by the DSP to sample the data. The switching circuit multiplies the received data with the clock signal to produce lower intermediate frequencies, which can then be adequately sampled at the DSP at the reduced sampling rate per the Nyquist sampling criteria.

Abstract: Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Abstract: An improved implantable medical device system having dual coils in one of the devices in the system is disclosed. The dual coils are used preferably in an external device such as an external controller or an external charger. The dual coils are wrapped around axes that are preferably orthogonal, although other non-zero angles could be used as well. When used to transmit, the two coils are driven (for example, with FSK-modulated data when the transmitting data) out of phase, preferably at 90 degrees out of phase. This produces a magnetic field which rotates, and which reduces nulls in the coupling between the external device and the receiving coil within the implanted device. Moreover, implementation of the dual coils to transmit requires no change in the receiver circuitry of the implanted device. Should the device with dual coils also receive transmissions from the other device (e.g.

Abstract: Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Abstract: By incorporating magnetic field sensing coils in an external charger, it is possible to determine the position of an implantable device by sensing the reflected magnetic field from the implant. In one embodiment, two or more field sensing coils are arranged to sense the reflected magnetic field. By comparing the relative reflected magnetic field strengths of the sensing coils, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.

Abstract: Receiver and demodulation circuitry for an external controller for an implantable medical device is disclosed. The circuitry comprises two high Quality-factor band pass filters (BFPs) connected in series. Each BFP is tuned to a different center frequency, such that these center frequencies are outside the band of frequencies transmitted form the IMD. The resulting frequency response is suitably wide to receive the band without attenuation, but sharply rejects noise outside of the band. The resulting filtered signal is input to a comparator to produce a square wave of the filtered signal, which maintains the frequencies of the received signal and is suitable for input to a digital input of a microcontroller in the external controller. Demodulation of the square wave occurs in the microcontroller, and involves assessing the time between transitions in the square wave. These transmission timings are compared to expected transition times for the logic states in the transmitted data.

Abstract: Receiver and digital demodulation circuitry for an external controller for communicating with an implantable medical device (IMD) is disclosed. A Digital Signal Processor (DSP) is used to sample received analog data transmitted from the IMD at a lower rate than would otherwise be required for the frequency components in the transmitted data by the Nyquist sampling criteria. To allow for this reduced sampling rate, the incoming data is shifted to a lower intermediate frequency using a switching circuit. The switching circuit receives a clock signal, which is preferably but not necessarily the same clock signal used by the DSP to sample the data. The switching circuit multiplies the received data with the clock signal to produce lower intermediate frequencies, which can then be adequately sampled at the DSP at the reduced sampling rate per the Nyquist sampling criteria.

Abstract: By incorporating magnetic field sensing coils in an external charger, it is possible to determine the position of an implantable device by sensing the reflected magnetic field from the implant. In one embodiment, two or more field sensing coils are arranged to sense the reflected magnetic field. By comparing the relative reflected magnetic field strengths of the sensing coils, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.

Abstract: By incorporating magnetic field sensing coils in an external charger, it is possible to determine the position of an implantable device by sensing the reflected magnetic field from the implant. In one embodiment, two or more field sensing coils are arranged to sense the reflected magnetic field. By comparing the relative reflected magnetic field strengths of the sensing coils, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.

Abstract: By incorporating magnetic field sensing coils in an external charger, it is possible to determine the position of an implantable device by sensing the reflected magnetic field from the implant. In one embodiment, two or more field sensing coils are arranged to sense the reflected magnetic field. By comparing the relative reflected magnetic field strengths of the sensing coils, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.