Circuit Device Voltage Correction for Display Drivers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In display drivers, the fluctuation of gradation voltages due to increased load causes errors in data voltages, leading to inaccuracies in electro-optical panel operations.
Innovation Solution
A circuit device with a gradation voltage generation circuit and a correction processing circuit that groups gradation voltages and performs correction processing based on the number of input display data belonging to each group, reducing voltage errors by adjusting the data on the output side.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If multiple D/A converter circuits commonly share the same output line to select gradation voltages, then the device complexity is reduced, but the load on the output line increases causing gradation voltage fluctuation and data voltage errors
Solution Approach 1:
The patent segments the gradation voltages into multiple groups (first group and second group) based on their bit significance. The D/A converter circuits are divided into first D/A converter circuits that handle lower-bit gradation voltages and second D/A converter circuits that handle higher-bit gradation voltages. This segmentation allows independent control and correction of voltage fluctuations in different groups, reducing the impact of load variations on overall voltage accuracy while maintaining a shared output line structure.
2Productivity
If the number of D/A converter circuits selecting the same gradation voltage increases, then more pixels can be driven simultaneously, but the load on the output line increases causing gradation voltage fluctuation
Solution Approach 1:
The patent implements a feedback mechanism where the number of D/A converter circuits selecting gradation voltages from each group is counted and used to generate correction values. When the load on an output line increases causing voltage fluctuation, the correction values adjust the selected gradation voltages to compensate for the fluctuation. This feedback loop maintains voltage precision even when multiple pixels are driven simultaneously with high productivity.
3Measurement precision
If correction processing is performed on all input display data, then voltage accuracy is improved, but the computational load increases
Solution Approach 1:
The patent applies correction processing selectively based on local conditions. Instead of correcting all input display data uniformly, the correction is applied only to data that requires it, determined by analyzing which group (first or second) each gradation voltage belongs to and counting the number of selectors in each group. This local quality approach improves voltage accuracy where needed while minimizing unnecessary computational power consumption.
Data Source
AI summary
A circuit device includes a gradation voltage generation circuit, a correction processing circuit, and a driving circuit. The correction processing circuit performs correction processing on input display data to output corrected display data. The driving circuit drives an electro-optical panel by outputting gradation voltages corresponding to the corrected display data based on the gradation voltages. The gradation voltages are grouped into first to k-th groups. At this time, the correction processing circuit determines, by analyzing which group of the first to the k-th groups each input display data belongs to, a number of the input display data belonging to each group, and performs the correction processing based on the determined number.