Magnetic Stripe Transmission Circuit with Dual Coils
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic stripe transmission (MST) circuits face challenges in operating at low currents due to smaller battery capacities in portable devices, leading to reduced recognition rates and increased rise time periods, which are difficult to address through changes in coil current or size.
Innovation Solution
The implementation of an MST circuit with two coils, where one coil is wound in a different direction, and a driver system that controls currents using voltage pulses to generate specific waveforms, reducing ripple and improving recognition rates without increasing coil size or current magnitude.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the battery capacity is reduced to miniaturize the electronic device, then the device size is reduced, but the maximum allowable current from the battery becomes smaller
Solution Approach 1:
The patent divides the single coil into two separate coils (first coil and second coil) that are connected in parallel. Each coil is driven by its own driver circuit, allowing independent control of current waveforms. This segmentation enables the system to achieve the required magnetic field strength through coordinated operation of multiple smaller coils rather than requiring a single large coil, thus resolving the contradiction between device miniaturization and power delivery capability.
2Strength
If the inductance of the MST circuit is increased to improve magnetic field strength, then the magnetic field strength is improved, but the rise time period of the current increases and recognition rate is reduced
Solution Approach 1:
The patent employs periodic voltage pulses to drive each coil, with each pulse generating a corresponding current waveform. The drivers apply pulsed voltage signals that create rapid current rises followed by controlled decay, producing periodic magnetic field variations. This periodic action allows the system to achieve strong magnetic field signals at specific time intervals without requiring continuously high inductance, thus resolving the contradiction between magnetic field strength and rise time.
Solution Approach 2:
The patent uses dynamic control of voltage pulses applied to each coil, where the amplitude, width, and timing of pulses are adjusted to optimize current waveform characteristics. The driver circuits dynamically switch transistors to control current flow, enabling rapid establishment of magnetic fields when needed while managing inductance effects. This dynamic approach allows optimization of both magnetic field strength and rise time based on operational requirements.
3Strength
If the current magnitude flowing through the coil is increased to improve magnetic field strength, then the magnetic field strength is improved, but the battery capacity requirement increases
Solution Approach 1:
By dividing the total current requirement into two separate coils driven in parallel, each coil carries a portion of the total current. This segmentation allows the system to achieve the required combined magnetic field strength without requiring either coil to handle the full current load that a single coil would need, thus reducing the peak current demand on the battery and resolving the contradiction between magnetic field strength and battery capacity requirements.
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
This solution enables the MST circuit to operate effectively at low currents, enhancing recognition rates by generating wider transition widths in current waveforms and larger voltage measurements, suitable for devices with small battery capacities.
Implementation Method 1
The MST circuit may generate magnetic stripe data by controlling the magnitude of a current flowing through a coil
Data Source
AI summary
A magnetic stripe transmission (MST) apparatus that improves a recognition rate and operates at a low current is provided. The apparatus includes a first coil disposed between a first power supply source and a second power supply source, and wound in a first direction, a second coil connected in parallel to the first coil, disposed between the first power supply source and the second power supply source, and wound in a second direction, a first driver disposed between the first coil and the second power supply source, and configured to control a first current of the first coil according to a first voltage pulse supplied by a first pulse supply source, and a second driver disposed between the second coil and the second power supply source, and configured to control a second current of the second coil according to a second voltage pulse supplied by a second pulse supply source.