Capacitive Tamper Detection Enclosure for Circuitry

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Electronic systems are vulnerable to physical tampering, which can compromise sensitive intellectual property assets, as existing tamper-proof solutions are not effective against reverse engineering and hardware-based attacks.

Innovation Solution

A secure enclosure for circuitry using capacitive sensing, comprising a platform, charge source, first and second capacitive plates, and a capacitive sensor, where the capacitive sensor detects changes in capacitance between the plates to determine tampering attempts, and the control unit mediates input and output to prevent unauthorized access.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional tamper-proof solutions (potting, electro-mechanical switches, PCB enclosures) are used, then physical protection is provided, but they are vulnerable to reverse engineering and hardware-based attacks

Engineering Contradiction:

Improvetamper resistanceVSAvoidvulnerability to reverse engineering

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces mechanical tamper detection mechanisms (electro-mechanical switches, physical enclosures) with a capacitive sensing system that uses electrical fields to detect tampering. The capacitive sensor detects changes in capacitance caused by tampering activities, providing detection capabilities that are not susceptible to the same reverse engineering techniques that compromise mechanical systems.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The system monitors changes in electrical parameters (capacitance) to detect tampering. By measuring capacitance changes between the first and second capacitive plates, the system can detect physical interference, drilling, or other tampering attempts without relying on mechanical switches or physical barriers that can be reverse engineered.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If capacitive sensing is implemented with charged plates, then tamper detection capability is improved, but device complexity increases

Engineering Contradiction:

Improvetamper detection precisionVSAvoidenclosure structure complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The capacitive plates serve multiple functions: they create the electrical field for sensing, act as part of the enclosure structure, and provide the sensing surface. This multi-functionality reduces overall device complexity compared to having separate sensing elements and structural components.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the capacitive sensing elements with the enclosure structure itself. The first and second capacitive plates are integrated into the enclosure, eliminating the need for separate sensing components and reducing overall system complexity while maintaining detection precision.

Inventive Principle:

Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Effectively prevents physical tampering by detecting changes in capacitance, thereby securing sensitive assets within the enclosure and disabling them if tampering is detected, reducing the risk of intellectual property theft or manipulation.

Implementation Method 1

The capacitive sensor is electrically connected to the first capacitive plate and configured to determine when a capacitance between the first and second capacitive plates is changed

Methodology Applied

Scientific EffectCapacitance: Capacitance

Implementation Method 2

The second capacitive plate is configured so that there is an electric potential difference between the first capacitive plate and the second capacitive plate

Methodology Applied

Scientific EffectElectric Field: Electric Field

Data Source

PatentUS11805596B2Tamper detection

Publication Date: 2023.10.31 TEXAS INSTRUMENTS INC

AI summary

In described examples, an enclosure for circuitry includes a platform, a charge source, a first capacitive plate, a second capacitive plate, and a capacitive sensor. The circuitry is fixedly coupled to the platform. The first capacitive plate is also fixedly coupled to the platform, and either alone, or together with the platform, surrounds a volume containing the circuitry and the charge source, the charge source electrically coupled to and configured to charge the first capacitive plate. The second capacitive plate is fixedly coupled to the platform without touching the first capacitive plate, and either alone, or together with the platform, surrounds the first capacitive plate. The second capacitive plate is configured so that there is an electric potential difference between the first capacitive plate and the second capacitive plate. The capacitive sensor is electrically connected to the first capacitive plate and configured to determine when a capacitance between the first and second capacitive plates is changed.