Apparatus for high speed data communication between an external medical device and an implantable medical device

• US 5,383,912 A
• Filed: 05/05/1993
• Issued: 01/24/1995
• Est. Priority Date: 05/05/1993
• Status: Expired due to Term

• Current Assignee: Intermedics Incorporated (Boston Scientific Corporation)
• Original Assignee: Intermedics Incorporated (Boston Scientific Corporation)
• Inventors: Armstrong, Randolph K., Cox, Timothy J.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US08/058,752
• Time in Patent Office: 629 Days
• Field of Search: 128/898, 128/903, 128/631, 128/697, 607/32, 607/60
• US Class Current: 607/32
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: Y10S 128/903 Radio telemetry

Abstract

A method of communicating data between an external device and an implantable medical device wherein a first pulse is transmitted as electromagnetic energy from one device to the other, is received and stored as electrostatic energy in the second device and, after a delay period representing data to be communicated, the stored energy is released and transmitted as electromagnetic energy back to the first device. A communications circuit in the implantable device for accomplishing the method includes an antenna coil, a non-linear electronic component in circuit communication with the antenna coil, a storage capacitor in circuit communication with the antenna coil and non-linear electronic component for storing energy received by the antenna coil, and a switch for selectively connecting the charged storage capacitor and the antenna coil to discharge the charge stored in the capacitor into the antenna coil.

Claims

1. A method of bi-directionally and simultaneously communicating data between an external device and an implantable medical device, comprising the steps of:

generating a first plurality of time delay intervals each having a length representative of a corresponding data value to be communicated from the external device to the implantable medical device;

generating a second plurality of time delay intervals each having a length representative of a corresponding data value to be communicated from the implantable medical device to the external device;

transmitting a first train of pulses of electromagnetic energy from the external device to the implantable medical device by transmitting each, except the first, pulse of said first train of pulses after a respective time delay interval following transmission of an immediately preceding pulse of said first train of pulses, the respective time delay interval being a respective one of said first plurality of time delay intervals;

receiving in the implantable medical device the first train of pulses of electromagnetic energy;

transmitting a second train of pulses of electromagnetic energy from the implantable medical device to the external device by transmitting each pulse of said second train of pulses after a respective time delay interval following receipt of an immediately preceding pulse of said first train of pulses, the respective time delay interval being a respective one of said second plurality of time delay intervals; and

receiving in the external device the second train of pulses of electromagnetic energy.

2. A method of bi-directionally and simultaneously communicating data between an external device and an implantable medical device, comprising the steps of:

generating a first plurality of time delay intervals each having a length representative of a corresponding data value to be communicated from the external device to the implantable medical device;

generating a second plurality of time delay intervals each having a length representative of a corresponding data value to be communicated from the implantable medical device to the external device;

transmitting a first train of pulses of electromagnetic energy from the external device to the implantable medical device by transmitting each, except the first, pulse of said first train of pulses after a respective time delay interval following receipt of an immediately preceding pulse of a second train of pulses, the respective time delay interval being a respective one of said first plurality of time delay intervals;

receiving in the implantable medical device the first train of pulses of electromagnetic energy;

transmitting said second train of pulses of electromagnetic energy from the implantable medical device to the external device by transmitting each pulse of said second train of pulses after a respective time delay interval following receipt of an immediately preceding pulse of said first train of pulses, the respective time delay interval being a respective one of said second plurality of time delay intervals; and

receiving in the external device the second train of pulses of electromagnetic energy.