Bias Voltage Generating Circuit with Preliminary Charge Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bias voltage generating circuits for liquid crystal panels face challenges in returning to a predetermined voltage within a short time frame due to increased input capacitances and wiring capacitances, leading to high power consumption when increasing reference current to achieve faster return times.
Innovation Solution
The proposed bias voltage generating circuit incorporates a voltage return unit with a charge storing element and a drive controller that switches the first switch from OFF to ON before power OFF to store bias voltage and from ON to OFF before power ON to discharge it, allowing for high-speed return to a predetermined voltage without increasing reference current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the reference current is increased to achieve faster return time, then the return speed to predetermined voltage is improved, but the power consumption increases
Solution Approach 1:
The voltage return unit performs preliminary action by storing bias voltage in a charge storing element before the power ON state begins. This pre-charging process allows the circuit to quickly return to predetermined voltage without requiring high reference current during the actual return period, thus resolving the contradiction between fast return speed and low power consumption.
2Loss of energy
If the frequency of power saving processing is increased, then the power consumption reduction effect is improved, but the returning process from power-saving state to operation state becomes slower
Solution Approach 1:
By pre-storing bias voltage in the charge storing element during the power OFF state, the circuit eliminates the time-consuming voltage buildup process during return. This enables frequent power saving processing without sacrificing return speed, allowing the system to maximize power consumption reduction while maintaining fast returning capability.
3Duration of action of stationary object
If the input capacitance and wiring capacitance are increased, then the voltage holding capability is improved, but the return time to predetermined voltage is extended
Solution Approach 1:
The charge storing element acts as an intermediary that decouples the voltage holding function from the return speed. It stores bias voltage independently, then rapidly discharges it to the output node when needed, allowing the circuit to maintain both high voltage holding capability and fast return time despite increased capacitance values.
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 approach enables the bias voltage to return quickly to a predetermined voltage, reducing the time required for the power-saving state to switch back to the operational state, thereby minimizing power consumption and improving efficiency.
Implementation Method 1
a voltage return unit with a charge storing element and a first switch for connecting or disconnecting the charge storing element to a bias voltage output wiring
Data Source
AI summary
In a bias voltage generating circuit for outputting through switching over a plurality of bias voltages and standby voltages provided for the respective bias voltages, a voltage return unit is provided for each bias voltage, and charges stored in the voltage return unit are supplied before power ON starts so that the bias voltage is approximated to a predetermined voltage. A drive controller drives the voltage return unit and a standby voltage generator, and a period of driving control is arbitrarily set by a register.