Reconfigurable Current-Sensing Amplifier for Wide Impedance Ranges

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing amplifier systems lack flexibility in measuring a wide range of currents from devices with varying impedances, often requiring dedicated components and experiencing instability under certain load conditions.

Innovation Solution

A controllable sensing circuit with selectable resistors and capacitors, coupled with a control circuit, allows the amplifier system to configure impedance and operate as a reconfigurable analog front-end, enabling measurement of currents spanning multiple decades across various impedance values, and includes a processing system for digital feedback and control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If dedicated components are used for measuring specific current ranges, then measurement precision is improved, but device complexity and adaptability worsen

Engineering Contradiction:
Improvecurrent measurement precisionVSAvoidadaptability to various impedance values
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The sensing circuit is made dynamically reconfigurable through switches that can selectively connect different resistor and capacitor components. This allows the circuit impedance to be dynamically adjusted to match different DUT impedance values, enabling a single amplifier system to accurately measure currents across multiple decades while adapting to various device characteristics

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The amplifier system is designed with universal sensing circuitry that can function across multiple measurement ranges and impedance conditions. By incorporating selectable resistor values (R1, R2, R3) and capacitor values (C1, C2, C3), the same circuit architecture serves multiple measurement purposes, eliminating the need for separate dedicated components for each current range

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Stability of the object's composition

If fixed impedance sensing circuit is used, then circuit stability is improved, but adaptability to different DUTs worsens

Engineering Contradiction:
Improvecircuit stabilityVSAvoidadaptability to different DUTs
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The sensing circuit transitions from a fixed impedance design to a dynamically reconfigurable one. Switches controlled by the processing system enable selective connection of different R and C components, allowing the circuit to adapt its impedance characteristics to match different DUTs while maintaining stability through controlled reconfiguration rather than random variation

Inventive Principle:
Principle #15Dynamics

3Adaptability or versatility

If reconfigurable sensing circuit with selectable components is implemented, then adaptability to various impedances is improved, but device complexity increases

Engineering Contradiction:
Improveadaptability to various impedance valuesVSAvoidcircuit configuration complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The sensing circuit is segmented into modular components (resistors R1-R3, capacitors C1-C3, and switches) that can be independently selected and configured. This segmentation allows the complex reconfiguration task to be broken down into manageable discrete element selections, simplifying the overall control logic while maintaining high adaptability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The processing system acts as an intermediary that automatically controls the switches based on detected DUT characteristics. This intermediary layer shields the user from the complexity of manual component selection and configuration, allowing the system to achieve high adaptability through automated control rather than requiring complex user interaction

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3650868B1Amplifier systems for measuring a wide range of current
Publication Date: 2022.06.01 ANALOG DEVICES INT UNLTD CO
  • EP3650868B1 patent drawingFigure 1A~1B
  • EP3650868B1 patent drawingFigure 1C
  • EP3650868B1 patent drawingFigure 2

AI summary

Amplifier systems for measuring a wide range of current are provided herein. In certain embodiments, an amplifier system includes a controllable sensing circuit, a first amplifier including an output configured to drive a device under test (DUT) through the controllable sensing circuit, and a second amplifier including an input coupled to the controllable sensing circuit and operable to generate a measurement signal indicating an amount of measured current of the DUT. The amplifier system further includes a control circuit operable to control a configuration or mode of the controllable sensing circuit suitable for a particular type of DUT.