Pacesetter, Inc.

Texas Instruments Corporation

Eric Christophe Labbe

Benjamin T Persson

Qiong M Li

Will Heng Zhang Lui

Erno H Klaassen

Dean P Andersen

Christian M Sauer

Paul F Illegems

Klaus Krogsgaard

Jeffrey Wallace Berwick

Cliff C Nixon

Cheng Hsun Lin

Shuo Li

A system is provided that includes electrodes configured to be implanted in a body, and a pulse generator (PG) circuitry to deliver a stimulus to one or more of the electrodes. The system also includes sensing circuitry configured to define a sensing channel between one or more of the electrodes to sense signals indicative of a physiologic activity of interest, and the sensing circuitry further configured to collect a calibration signal over the sensing channel. The sensing circuitry and PG circuitry are housed within an implantable medical device (IMD). The system also includes one or more processors configured to determine a signal characteristic of interest (COI) of the calibration signal. The one or more processors are also configured to compare a signal COI of the stimulus to the signal COI of the calibration signal, and adjust a parameter of the sensing circuitry or PG circuitry based on the comparison.

Method and system for calibrating sensing circuitry of an implanted medical device

Described herein is a fully-differential receiver for use with an implantable medical device (IMD) and configured to receive conducted communication signals that are transmitted by another IMD or an external device. The fully-differential receiver includes a fully-differential preamplifier, a fully-differential buffer, a first comparator, a second comparator, and an AC coupling network coupled between differential outputs of the fully-differential buffer and a coupled together differential pair of inputs of the first and second comparators. A differential pair of inputs of the fully-differential receiver comprise the differential pair of inputs of the fully-differential preamplifier, and a differential pair of outputs of the fully-differential receiver comprise a first output of the first comparator and a second output of the second comparator. In order to conserve power, the fully-differential receiver is selectively changed from operating in a first mode to operating in a second mode, and vice versa.

Fully-differential receiver for receiving conducted communication signals

Described herein is a fully-differential preamplifier comprising an input differential pair, an output current load, and a current source. The current source is coupled between the input differential pair and a low voltage rail and configured to control whether the fully-differential preamplifier is operating in a first mode or a second mode, wherein the preamplifier draws more current when operating in the second mode compared to when operating in the first mode. The input differential pair is coupled between the output current load and the current source. The output current load is coupled between a high voltage rail and the input differential pair. The input differential pair comprise positive and negative inputs of the fully-differential preamplifier. Nodes where the input differential pair and the output current load are coupled to one another comprise positive and negative outputs of the fully-differential preamplifier.

Fully-differential preamplifier

Described herein are implantable medical devices (IMDs), and methods for use therewith, that enable monitoring of impedance associated with a pathway (e.g., including a lead) used to selectively deliver stimulation pulses to patient tissue. A method involves measuring or storing a first voltage indicative of the energy stored on a reservoir capacitor (Cres) just prior to a stimulation pulse being delivered via the pathway, as well as measuring or storing a second voltage indicative of the energy stored on the Cres just after the stimulation pulse is delivered via the pathway. The method also includes monitoring the impedance associated with the pathway based on a difference between the first and second voltages, which may involve determining a count value indicative of how long it takes to discharge the first voltage to drop to the second voltage, wherein the count value is a surrogate of the impedance associated with the pathway.

Lead impedance monitoring for an implantable medical device

Example implantable cardiac stimulation devices, pulse generators, and methods providing enhanced cardiac pacing energy are disclosed herein. In an example, an implantable cardiac stimulation device may include a pulse generator having a pacing output node providing cardiac pacing pulses to be applied to a heart of a patient. The pulse generator may include a pulse voltage regulator that receives a pacing signal and generates cardiac pacing pulses at an output of the pulse voltage regulator according to the pacing signal. The pulse voltage regulator may receive a supply voltage to generate cardiac pacing pulses at the supply voltage, gated by the pacing signal. The pulse generator may further include routing circuitry to route the output of the pulse voltage regulator to the pacing output node of the pulse generator while the pulse generator is in a first operating mode, and to route the supply voltage, gated by the pacing signal, to the pacing output node of the pulse generator while the pulse generator is in a second operating mode.

Cardiac pacing energy enhancement

The present disclosure provides a cardiac pacing system. The cardiac pacing system includes a right atrial ring electrode, a right atrial tip electrode, a right ventricle ring electrode, and a pacing integrated circuit (IC) including a first pace output node electrically coupled to the right atrial ring electrode, a pace return node electrically coupled to the right atrial tip electrode, and a second pace output node electrically coupled to the right ventricle ring electrode, wherein the pacing IC has a fast discharge configuration that facilitates reducing or eliminating a DC rectification current generated from RF interference during a fast discharge phase.

Systems and methods for fast discharge in pacing circuits during RF interference

Described herein are implantable cardiac stimulation devices, and methods for use therewith. A pacing channel of such a device includes a pace output terminal, a pulse generator and at least two pace return electrode terminals. The pace output terminal is coupleable to an electrode for use as an anode. The pulse generator is configured to selectively output an electrical stimulation pulse to the pace output terminal. Each of the pace return electrode terminals is coupleable to a separate one of at least two further electrodes for use as a cathode. Switching circuitry selectively couples any one of the pace return electrode terminals of the pacing channel to the pace return capacitor of the pacing channel at a time, thereby enabling the pace return capacitor to be shared by at least two of the pace return electrode terminals of the pacing channel. Additional embodiments are also disclosed herein.

Implantable cardiac stimulation devices, and methods of use therewith, that use assignable pace return capacitors

A circuit for diminishing mismatch effects between at least two switched signals includes at least three processing circuits configured to receive at least two switched signals such that each of the switched signals is associated with one of the processing circuits leaving at least one unassociated processing circuit. A controller circuit is configured to switch one of the switched signals to be associated with one of the unassociated processing circuit(s) upon at least one specified interval such as, for example, at a transition of the switched signal. The circuit may be incorporated into an audio amplifier configured to provide information carried on the switched signals to one or more speakers that provide an audio output. A one-processor circuit approach includes switching frames of a switched signal between positive and negative inputs of a processor circuit to average out errors introduced by the processor circuit.

Method and apparatus for diminishing mismatch effects between switched signals

In accordance with the present invention, there is provided a circuit and method for providing a switchable strong pulldown for a power FET in an off state to avoid inadvertent or false turn ons. A strong pulldown is provided to the gate of a power FET to avoid inadvertent turn on during output swings. In other cases, the gate of the power FET is pulled down weakly to reduce EMI and voltage noise in the circuit. In a particular exemplary embodiment, the present invention provides a circuit and method for obtaining a strong pulldown on the gate of a power FET in an off state, while providing a weak pulldown during turn on to turn off transitions. The invention avoids false turn ons during fast output transitions while maintaining relatively high EMI protection.

Circuit and method for transistor turn-off with strong pulldown

A system for detecting a direct current (DC) component of a pulse-width modulated (PWM) signal includes a modulator configured to provide at least one PWM signal to an input of an amplifier. A DC detector is configured to detect a DC component of a selected one of the at least one PWM signal as a function of a switching frequency of the selected PWM signal. The DC detector provides at least one report signal that indicates a level of the DC component of the selected PWM signal relative to a predetermined threshold.

Methods and system for detecting DC output levels in an audio system

An apparatus for controlling a power converter operating in response to a modulating signal during successive switching cycles includes: (a) A signal sensor coupled with the converter and sensing an extant signal during the extant cycle. (b) A signal level predictor coupled for receiving a reference signal and establishing a predicted level for the extant switching cycle. (c) A comparer coupled with the signal sensor and the signal level predictor for presenting a first output signal when the extant signal and the predicted signal level have a first relationship and for presenting a second output signal when the extant signal and the predicted signal level have a second relationship. (d) A control unit coupled with the comparer and with the converter for interrupting presentation of the modulating signal to the converter device when the comparing unit presents a selected one of the first and second output signals.

Growing community of inventors

Sunnyvale, CA, United States of America

Eric Christophe Labbe