Shared RFID and Wireless Charging Circuit for Space-Limited Devices

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The integration of an RFID card reader function into electronic devices is challenging due to limited space and increasing portability requirements, as existing devices have a large RFID circuit layout.

Innovation Solution

An electronic device incorporating a wireless charging circuit, antenna module, and matching circuit with specific capacitors and modulation circuits, allowing for shared hardware to support wireless charging, RFID card reading, and RFID card simulation modes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If an RFID circuit is integrated into an electronic device, then the device gains RFID card reader functionality, but the device volume increases due to the large layout area required for the RFID circuit

Engineering Contradiction:
ImproveRFID card reader functionalityVSAvoiddevice volume
Core Design Contradiction:
Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent combines the RFID circuit and wireless charging circuit into a single integrated structure, sharing common components such as the antenna, resonant capacitor, and control unit. This merging allows the device to achieve both RFID card reader functionality and wireless charging capability without proportionally increasing the device volume, as the shared components serve dual purposes.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The antenna module is designed to serve multiple functions: it acts as both the RFID antenna for card reading operations and the wireless charging antenna for energy transmission. The resonant capacitor and control circuitry are also configured to support both RFID modulation and wireless charging protocols, enabling a single component to perform multiple roles and reduce overall device complexity and size.

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

2Reliability

If separate RFID and wireless charging circuits are used, then each function operates independently with high reliability, but the device complexity increases due to multiple independent circuits

Engineering Contradiction:
Improvefunction operation reliabilityVSAvoidcircuit structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The integrated circuit is segmented into distinct functional modules: an RFID module for card reading operations and a wireless charging module for power transmission, both controlled by a unified control unit. This segmentation allows each module to operate independently with dedicated signal paths and control logic, maintaining functional reliability while reducing overall circuit complexity through shared infrastructure.

Inventive Principle:
Principle #1Segmentation

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

Enriches the functionality of electronic devices by integrating RFID card reader capabilities without significantly increasing device volume, through efficient sharing of components.

Implementation Method 1

A 125K low-frequency radio frequency identification (Radio Frequency Identification, RFID) technology is a near field communication identification technology with a carrier frequency of 125K to 135K hertz

Methodology Applied
Scientific EffectElectromagnetic Induction: Electromagnetic Induction

Implementation Method 2

A wireless charging technology is a wireless energy transmission technology based on a carrier frequency of 110K to 190K hertz

Methodology Applied
Scientific EffectElectromagnetic Induction: Electromagnetic Induction

Data Source

PatentEP4404100B1Electronic device and control method
Publication Date: 2026.01.21 VIVO MOBILE COMM CO LTD
  • EP4404100B1 patent drawingFigure 1
  • EP4404100B1 patent drawingFigure 2
  • EP4404100B1 patent drawingFigure 3

AI summary

This application provides an electronic device and a control method, and belongs to the field of electronic technologies. The electronic device includes a wireless charging circuit, an antenna module, and a matching circuit, where the matching circuit includes a first resonant capacitor, a first load modulation capacitor, a second load modulation capacitor, and an envelope detection circuit, and the wireless charging circuit includes a microcontroller unit, a demodulation circuit, a first half-bridge drive circuit, a second half-bridge drive circuit, a first load modulation circuit, and a second load modulation circuit, where the first half-bridge drive circuit is electrically connected to the second half-bridge drive circuit sequentially by using the antenna module and the first resonant capacitor, the first load modulation circuit is separately electrically connected to the antenna module and the envelope detection circuit by using the first load modulation capacitor, the second load modulation circuit is separately electrically connected to the antenna module, the first resonant capacitor, and the envelope detection circuit by using the second load modulation capacitor, and the envelope detection circuit is further electrically connected to the demodulation circuit.