Micro-charge pulse injection circuit for cochlear implants

Solution Overview

Problem

Conventional cochlear implants require high voltage supplies and large current sources to deliver constant-current pulses, leading to inefficiencies and increased size, which limits their effectiveness in stimulating nerve cells for sound perception.

Innovation Solution

The use of micro-charge pulses, generated by a micro-charge pulse injection circuit with an H-Bridge configuration, delivers discrete sets of pulses that collectively cause nerve cells to fire, eliminating the need for constant-current pulses and reducing the size and power consumption of the stimulation circuit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If constant-current pulses are delivered using high voltage supplies and large current sources, then nerve cells can be stimulated for sound perception, but the device size and power consumption increase

Engineering Contradiction:

Improvenerve cell stimulation effectivenessVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent segments the stimulation approach by delivering multiple discrete micro-charge pulses instead of a single constant-current pulse. Each micro-charge pulse contributes a portion of the total charge needed to stimulate the nerve cell, and the cumulative effect of these segmented pulses achieves the desired stimulation while using smaller, more efficient circuitry

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent changes the stimulation parameters from continuous constant-current pulses to discrete micro-charge pulses with specific charge quantities. By controlling the charge delivered in each micro-pulse and the number of pulses delivered, the system achieves effective nerve stimulation with reduced power consumption and smaller circuitry

Inventive Principle:

Principle #35Parameter changes

2Reliability

If constant-current pulses are delivered using high voltage supplies and large current sources, then nerve cells can be stimulated for sound perception, but the device complexity and size increase

Engineering Contradiction:

Improvenerve cell stimulation effectivenessVSAvoidcircuitry size

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the stimulation approach by delivering multiple discrete micro-charge pulses instead of a single constant-current pulse. Each micro-charge pulse contributes a portion of the total charge needed to stimulate the nerve cell, and the cumulative effect of these segmented pulses achieves the desired stimulation while using smaller, more efficient circuitry

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent replaces the mechanical/electrical system of high voltage supplies and large current sources with a micro-charge pulse injection circuit that uses capacitive coupling and switched capacitor networks. This substitution eliminates the need for bulky power supply components while achieving the same nerve stimulation effect

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS10342975B2Micro-charge stimulation

Publication Date: 2019.07.09 COCHLEAR LIMITED

AI summary

Presented herein are stimulation techniques for implantable tissue-stimulating systems. The stimulation techniques generate and deliver sets of micro-charge pulses to a recipient. The micro-charge pulses within a set collectively cause the firing of a recipient's nerve cell(s).