Transformer-Based Touch Sensor Excitation for Active Stylus Power Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Active styli used with touch-sensitive devices require significant power to generate stimulation signals, leading to high power consumption and reduced battery life, particularly in portable devices.
Innovation Solution
The implementation of a magnetic drive system within the active stylus, utilizing a transformer to generate high output voltage from logic-level input pulses, with distributed capacitance and resonance acting as a low-pass filter to create a clean output waveform, and autotransformer designs to optimize power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional active stylus designs are used to generate stimulation signals, then effective touch sensor excitation is achieved, but power consumption increases significantly
Solution Approach 1:
The patent replaces traditional electronic voltage boosting mechanisms with a magnetic field-based transformer system. Logic-level signals (3.3V or 5V) are converted to high-voltage stimulation signals through magnetic induction in the transformer, eliminating the need for complex booster regulators and significantly reducing power consumption while maintaining effective stimulation signal generation.
Solution Approach 2:
The invention changes the operating voltage parameters by using logic-level input signals (3.3V/5V) that are transformed into the required high-voltage output through the transformer. This parameter transformation approach allows operation at lower input voltages while achieving the necessary output voltage levels for stimulation, thereby reducing overall power consumption.
2Power
If booster regulators are used to generate high voltage output, then stimulation signals are produced, but device complexity increases
Solution Approach 1:
The patent substitutes complex electronic voltage regulation circuits with a simpler magnetic transformer-based system. The transformer naturally provides voltage transformation through magnetic induction, eliminating the need for booster regulators, MOSFETs, and associated control circuitry, thereby significantly reducing device complexity while maintaining high voltage output capability.
Solution Approach 2:
The invention extracts and removes the complex booster regulator components from the stylus circuitry, retaining only the essential transformer and logic-level signal generation components. This extraction simplifies the overall device architecture while preserving the necessary high voltage stimulation signal generation function.
3Use of energy by moving object
If logic-level signals are used as input, then power consumption is reduced, but output voltage amplitude decreases
Solution Approach 1:
The patent uses magnetic induction in a transformer to amplify logic-level input signals (3.3V or 5V) into high-voltage output signals. The magnetic field coupling in the transformer provides voltage transformation without requiring high input power, thus maintaining low power consumption while achieving the necessary high output voltage amplitude for effective stimulation.
Solution Approach 2:
The transformer acts as an intermediary device that converts logic-level electrical signals into high-voltage stimulation signals through magnetic field mediation. This intermediary transformation allows the system to operate at low input voltage levels (reducing power consumption) while producing the required high output voltage amplitude.
Data Source
AI summary
Input device power consumption can be reduced with a magnetic drive system. In some examples, the input device can include a transformer configured to generate a desired high output voltage from logic-level input pulses. In some examples, the distributed capacitance and associated resonance of the transformer can act as a low-pass filter, and can create a relatively clean output waveform from input logic signal waveforms. In some examples, the transformer can be an autotransformer. In some examples, to stabilize an amplitude of the output by sampling the output of the transformer and adjusting the input to the transformer based on the sampled output.