Voltage and Phase Compensation Circuit for Display EMI Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Alternating current signals from display panel driving circuits generate electromagnetic interference (EMI) that adversely affect peripheral devices.
Innovation Solution
A voltage and phase compensation circuit using inverting adders and a coupler to combine inverted panel signals with inverted feedback signals, creating a cancellation signal to minimize EMI.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If AC signals are output from the display panel driving circuit, then the display device can function normally, but electromagnetic interference (EMI) is generated that adversely affects peripheral devices
Solution Approach 1:
The patent generates an inverted AC signal that is intentionally designed to have the same amplitude and opposite phase to the original panel signal. This inverted signal is then combined with the original signal through a coupler, causing the harmful EMI components to cancel each other out while preserving the necessary display functionality. The harmful EMI is converted into a beneficial cancellation mechanism.
Solution Approach 2:
The patent applies preliminary anti-action by generating the inverted signal in advance before the EMI problem occurs. The inverted signal is prepared with the correct amplitude and phase relationship ahead of time, so that when combined with the original panel signal, it proactively neutralizes the EMI rather than reacting to it after the fact.
2Device complexity
If a simple signal output method is used, then the device complexity is low, but EMI cannot be effectively reduced
Solution Approach 1:
The patent merges the original panel signal with the inverted signal through a coupler to create a composite signal. This combination allows the beneficial display function to be maintained while the harmful EMI components cancel each other out. The merging of signals achieves EMI reduction without requiring complete system redesign.
Solution Approach 2:
The signal output is segmented into two components: the original panel signal and the inverted compensation signal. By separating the signal into these two distinct components that can be independently controlled and combined, the system achieves EMI cancellation while maintaining display functionality.
3Object-generated harmful factors
If voltage and phase alignment is achieved between signals, then EMI cancellation is effective, but the circuit requires precise control mechanisms
Solution Approach 1:
The patent uses signal inversion as the core mechanism to achieve voltage and phase alignment. By inverting the original signal to create a compensation signal with opposite phase but equal amplitude, the system achieves effective EMI cancellation. This inversion approach simplifies the control requirements compared to other phase alignment methods.
Data Source
AI summary
Disclosed is a voltage and phase compensation circuit and a display device including the same. The voltage and phase compensation circuit includes a first inverting adder configured to add and invert a plurality of panel signals to output a first inverted signal; a second inverting adder configured to add and invert the feedback signals obtained from delayed panel signals and the first inverted signal to output a second inverted signal; and a coupler configured to couple the first inverted signal and the second inverted signal.