Backlight Driving Circuit Using N-MOSFETs to Reduce On-Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional backlight driving circuits for LCDs face inefficiency due to high on-resistance in P-MOSFET transistors, leading to increased power consumption, heat generation, and higher costs, which affect the stability and brightness of the display.
Innovation Solution
The proposed solution involves a backlight driving circuit utilizing N-Channel mode metal-oxide-semiconductor field-effect transistors (N-MOSFETs) with a capacitor and follower circuitry, allowing for improved voltage regulation and reduced internal resistance, enabling efficient power management and lower operational temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If P-MOSFET transistors are used in the backlight driving circuit, then the circuit can operate, but the on-resistance is high causing increased power consumption and heat generation
Solution Approach 1:
The patent changes the key parameter of transistor type from P-MOSFET to N-MOSFET. This parameter change fundamentally alters the on-resistance characteristic, reducing it from high (in P-MOSFET) to low (in N-MOSFET), thereby resolving the contradiction between circuit operation and power consumption
Solution Approach 2:
The patent replaces expensive P-MOSFET transistors with cheaper N-MOSFET transistors. This substitution not only reduces cost but also improves efficiency by lowering on-resistance and power consumption, effectively addressing both economic and technical concerns
2Reliability
If P-MOSFET transistors are used in the backlight driving circuit, then the circuit can operate, but heat generation increases affecting stability
Solution Approach 1:
The patent changes the transistor type parameter from P-MOSFET to N-MOSFET, which fundamentally reduces on-resistance and consequently decreases I²R heat generation. This parameter change directly addresses the heat generation issue while maintaining circuit operation
Solution Approach 2:
The patent converts the inherent high on-resistance characteristic of P-MOSFET (which causes heat) into a benefit by replacing it with N-MOSFET's low on-resistance characteristic. The harmful heat generation is eliminated while the circuit continues to function, turning a problematic parameter into an advantage
3Reliability
If P-MOSFET transistors are used in the backlight driving circuit, then the circuit can operate, but the cost increases
Solution Approach 1:
The patent replaces expensive P-MOSFET transistors with cheaper N-MOSFET transistors. This substitution directly reduces component cost while maintaining circuit functionality, effectively resolving the contradiction between circuit operation and manufacturing cost
Solution Approach 2:
The patent changes the transistor type parameter from P-MOSFET to N-MOSFET, which not only improves electrical characteristics (lower on-resistance) but also reduces component cost, simultaneously addressing both operational reliability and manufacturing cost concerns
Data Source
AI summary
An exemplary backlight driving circuit (20) a first power supply (260); a second power supply (270); a signal output terminal (280); an AND gate (210); a follower (220); a capacitor (290); a reverser (230); a first transistor (240), which is a N-Channel mode metal-oxide-semiconductor field-effect transistor (N-MOSFET), having a gate electrode connected to an output end of the AND gate through the follower, a source electrode connected to the signal output terminal, a drain electrode connected to the first power supply; and a second transistor (250), which is a N-Channel mode metal-oxide-semiconductor field-effect transistor (N-MOSFET), having a gate electrode connected to the output end of the AND gate through the reverser, a source electrode connected to the ground, a drain electrode connected to the signal output terminal.