Method and apparatus for efficient power/data transmission
View Patent ↗A system, method and power/data transmission device comprising a coil having a high Q, a low-voltage driver and a high-voltage driver switchably coupled to the coil. The low-voltage driver and the high-voltage driver are controlled by a microcontroller and switch at about the same time thereby providing a modulated data signal for transmission. Furthermore, the system includes at least one implantable microstimulator coupled to the transmission device.
1. A power/data transmission device, comprising:
a coil having a high Q;
a low voltage driver capacitively coupled to the coil, said low voltage driver providing a carrier signal at a carrier frequency, said carrier signal defining carrier signal edges; and
a high voltage driver coupled to the coil, said high voltage driver providing a modulation signal, said modulation signal defining modulation signal edges, wherein the low voltage driver and the high voltage driver together provide a modulated data signal through the coil for transmission to a receiving device and wherein a modulation signal edge is timed to occur at about the same time as a carrier signal edge.
2. The power/data transmission device of claim 1 , wherein the coil has a low parasitic capacitance.
3. The power/data transmission device of claim 1 , wherein said low voltage driver and said high voltage driver causes an alternating current to flow in the coil, the coil current having zero crossings, a carrier signal edge and a modulation signal edge being timed to occur at a zero crossing.
4. The power/data transmission device of claim 1 , wherein the carrier signal is provided at a carrier frequency of about 2 MHz.
5. The power/data transmission device of claim 1 , wherein the low voltage driver comprises:
at least one low impedance switched-mode transistor.
6. The power/data transmission device of claim 1 , wherein the high voltage driver comprises:
at least one low impedance switched-mode transistor.
7. The power/data transmission device of claim 1 , wherein a modulation signal edge is synchronized with a carrier signal edge to produce the modulated data signal.
8. The power/data transmission device of claim 1 , wherein the modulated data signal is amplitude modulated.
9. A method of power/data transmission, comprising:
providing a high Q coil;
capacitively coupling low voltage driver to the coil, the low voltage driver providing a carrier signal at a carrier frequency, the carrier signal defining carrier signal edges;
coupling a high voltage driver to the coil, the high voltage driver providing a modulation signal, the modulation signal defining modulation signal edges, wherein the low voltage driver and the high voltage driver together provide a modulated data signal through the coil for transmission to a receiving device; and
timing a modulation signal edge to occur at about the same time as a carrier signal edge.
10. The method of claim 9 , wherein coupling the low voltage driver and the high voltage driver the coil, causes an alternating current to flow in the coil, the coil current having zero crossings, further comprising:
timing a carrier signal edge and a modulation signal edge to occur at a zero crossing.
11. The method of claim 9 , wherein the timing comprises:
synchronizing a modulation signal edge and a carrier signal edge, thereby producing a modulated data signal.
12. The method of claim 9 , wherein the carrier frequency is at about 2 MHz.
13. The method of claim 9 , wherein the modulation signal amplitude modulates the carrier signal.
14. An implantable medical device system comprising:
at least one implantable microstimulator;
a transmission device comprising:
a coil having a high Q;
a low voltage driver capacitively coupling a carrier signal, having defined signal edges, to the coil; and
a high voltage driver coupling a modulation signal, having defined signal edges, to the coil; and
a receiving device,
wherein the modulation signal modulates the carder signal and produces an amplitude modulated signal for transmission to the receiving device, and wherein a modulation signal edge is timed to occur at about the same time as a carrier signal edge.
15. The implantable medical device system of claim 14 , wherein the at least one microstimulator is less than 60 mm in longitudinal and less than 6 mm in lateral dimension.
16. The implantable medical device system of claim 14 , wherein coupling the low voltage driver and the high voltage driver to the coil causes an alternating current to flow in the coil, the coil current having zero crossings, a carrier signal edge and a modulation signal edge being timed to occur at a zero crossing.
17. A method of power/data transmission, comprising:
providing a high Q coil;
capacitively coupling a carrier signal to the coil, the carrier signal defining carrier signal edges;
coupling a modulation signal to the coil, the modulation signal defining modulation signal edges;
producing a modulated data signal by timing a modulation signal edge to occur at about the same time as a carrier signal edge; and
transmitting the modulated data signal through the coil to a receiving device.
18. The method of claim 17 , wherein coupling the low voltage driver and the high Voltage driver to the coil, causes An alternating current to floW in the coil, the coil current having zero crossings, further comprising:
timing a carrier signal edge and a modulation signal edge to occur at a zero crossing.
19. The method of claim 17 , wherein the carrier frequency is at about 2 MHz.
20. The method of claim 17 , wherein the modulation signal amplitude modulates the carrier signal.