Abstract: An electrical lead includes an elongate body having a proximal end portion and a distal end portion, a first electrode disposed adjacent and joined to the distal end portion of the elongate body, and a first conductor extending between the proximal end portion and the distal end portion of the elongate body and being electrically coupled to the first electrode. The medical electrical lead further comprises a second electrode disposed adjacent the first electrode and joined to the elongate body and a capacitive device electrically coupled to the first conductor and the second electrode.

Abstract: A medical device communications system uses subthreshold pulses, modulated to provide relatively high speed electrical communications with inexpensive external devices connectable to a body with the implant by surface leads.

Abstract: A medical device communications system uses subthreshold pulses, modulated to provide relatively high speed electrical communications with inexpensive external devices connectable to a body with the implant by surface leads.

Abstract: An electrical lead end cap includes a body defining a bore therein capable of receiving and retaining an end of an electrical lead and a connector capable of electrically coupling conductors leading to at least two electrodes. A method includes routing an electrical current induced in an electrical lead conductor disposed within body tissue to a plurality of electrodes, electrically coupled with the body tissue, via a circuit within an end cap attached to the electrical lead.

Abstract: An electrical lead includes an elongate body having a proximal end portion and a distal end portion, a first electrode disposed adjacent and joined to the distal end portion of the elongate body, and a first conductor extending between the proximal end portion and the distal end portion of the elongate body and being electrically coupled to the first electrode. The medical electrical lead further comprises a second electrode disposed adjacent the first electrode and joined to the elongate body and a capacitive device electrically coupled to the first conductor and the second electrode.

Abstract: Cyclic redundancy calculations are provided by operating on a data stream, e.g., a data stream in an implantable medical device, to perform a polynomial division thereon using one of a first cyclic redundancy code generator polynomial and a second cyclic redundancy code generator polynomial. The first cyclic redundancy code generator polynomial is a higher order polynomial than the second cyclic redundancy code generator polynomial and contains all terms of the second cyclic redundancy code generator polynomial. The polynomial division may be implemented using linear feedback shift register circuitry and circuitry to select between the use of the first or second cyclic redundancy code generator polynomial.

Abstract: A medical device communications system uses subthreshold pulses, modulated to provide relatively high speed electrical communications with inexpensive external devices connectable to a body with the implant by surface leads.

Abstract: A signal measuring system for use with an Implantable Medical Device (IMD) is provided for measuring physiologic signals having a relatively large effective dynamic range. In one embodiment, the system includes a High-Pass Filter (HPF), an Analog-to-Digital Converter (ADC), a Decimation Filter (DF), and a Compensation Filter (CF). The HPF receives an input signal that includes both the baseline wander imposed on a physiological signal. According to one aspect of the invention, the HPF attenuates low frequency components of the input signal, including a portion of the frequency band within the desired output signal bandwidth. The ADC then oversamples the output signal of the HPF. The DF receives the output samples from the ADC and generates output samples at rate that is at least twice the maximum frequency of the desired output signal. The CF then amplifies the low frequency end of the DF output samples.

Abstract: A method and apparatus including conditional add and conditional add/subtract instructions are provided for use in the instruction set of a medical device instruction processor. More specifically, the conditional add and add/subtract instructions are provided to add two operands if a predetermined condition is satisfied within the instruction processor hardware. Additionally, the conditional add/subtract instruction may be used to subtract one operand from another operand if the predetermined condition is not satisfied. These instructions are adapted for use in implementing an efficient, interruptible, firmware-controlled multiplication or division mechanism. The inventive system allows multiplication or division operations to be interrupted at various intermediate points during the multiplication or division operation to thereby reducing interrupt latency.

Abstract: An apparatus for communicating an electrical signal from a first portion of circuitry to a second, wherein there is no direct electrical contact between the two portions. In one embodiment, an EKG transmitter is disclosed which receives surface EKG signals from a patient, amplifies the EKG signals, modulates an oscillating carrier signal with the EKG signals, and transmits the resulting modulated signal across an optocoupled boundary. The modulated signal is then digitized directly, without demodulation, using phase progression digitization. The digitized information, from which the patient's EKG signal may be reconstructed, is then transmitted via a modem over conventional telephone lines. DC power drawn from the telephone line may be used directly to power the modem and phase progression digitizer, and may also be coupled via an isolating DC-to-DC transformer, to the frequency modulator and amplifier.