Charge Recovery Circuit for Memory-Type Liquid Crystal Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Memory-type liquid crystal displays require high voltage for operation, leading to increased power consumption due to the need for frequent voltage boosting, which is inefficient in battery-powered devices like handheld terminals.
Innovation Solution
A drive circuit configuration that includes a power-supply smoothing capacitor and a charge-and-discharge control circuit to collect and reuse electric charges, using a second battery to store discharged energy for subsequent voltage boosting, reducing the time needed for voltage setting and improving power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If voltage boosting is performed frequently for screen rewriting, then the liquid crystal display can be driven, but power consumption increases
Solution Approach 1:
The power supply smoothing capacitor stores electric charges in advance during periods when voltage boosting is not needed. This preliminary accumulation of energy allows the display to be driven without performing frequent voltage boosting operations, thereby reducing power consumption while maintaining the required drive voltage.
Solution Approach 2:
Instead of dissipating the electric charges accumulated in the power supply smoothing capacitor, the invention recovers and stores these charges in a storage battery. This recovery process converts what would be wasted energy into usable energy for subsequent drive operations, reducing overall power consumption.
2Productivity
If the time period for screen rewriting is shortened, then productivity improves, but the rate of voltage boosting increases and power consumption rises
Solution Approach 1:
The system performs preliminary voltage boosting and stores the boosted voltage in the power supply smoothing capacitor before screen rewriting operations. This allows rapid screen rewriting to be performed using pre-stored energy, avoiding the need to perform voltage boosting during the actual rewriting process and thereby maintaining high productivity without increasing power consumption.
3Reliability
If electric charges in the power supply smoothing capacitor are discharged naturally or forcibly, then voltage stabilization is achieved, but the accumulated electric charges are abandoned and power-saving property is reduced
Solution Approach 1:
The invention connects the power supply smoothing capacitor to a storage battery through a switch, enabling the recovery of electric charges that would otherwise be discharged and wasted. The storage battery captures these charges, converting them into stored energy that can be reused for subsequent drive operations, thereby eliminating energy loss while maintaining voltage stabilization.
Solution Approach 2:
The control circuit monitors the voltage state and manages the switching between the power supply smoothing capacitor and the storage battery. This feedback mechanism ensures that electric charges are transferred to the storage battery at appropriate times, optimizing both voltage stabilization and energy recovery without requiring continuous monitoring or complex control.
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 configuration effectively reduces power consumption by reusing stored electric charges, enhancing the image rendering capability and reducing the time required for voltage boosting, thus improving the overall efficiency of the liquid crystal display system.
Implementation Method 1
a power-supply smoothing capacitor
Implementation Method 2
using a second battery to store discharged energy
Data Source
AI summary
In a drive circuit for driving a liquid crystal display element with a memory property, electric charges accumulated in a power-supply smoothing capacitor at the subsequent stage of a booster circuit are collected effectively after electricity is supplied to the liquid crystal display element. The drive circuit for driving the liquid crystal display element with a memory property supplies a boosted voltage to the driver circuit by turning on a first switch circuit while the liquid crystal display element is being reset or while an image is being rendered, and causing electric charges accumulated in the power-supply smoothing capacitor to be discharged while collecting them into a second battery by turning on a second switch circuit during a period in which electric charges accumulated in the power-supply smoothing capacitor should be discharged.