Dual-Transistor Gate Control for Lower Transient On-State Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power transistors with switching functions face challenges in controlling gate operations during the transient On-period, leading to high energy loss and inefficiency.
Innovation Solution
A semiconductor device comprising a first and second transistor with controlled gate voltages, where the second transistor's emitter region length facing its gate is greater than the first transistor's, and a controller manages the gate voltages to minimize energy loss during transient states.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional voltage control strategies are used in single-gate transistors, then the device structure is simple, but energy loss during transient On-period cannot be sufficiently reduced
Solution Approach 1:
The invention divides the single transistor into two separate transistors (first transistor and second transistor) with independent gate control. This segmentation allows independent optimization of each transistor's emitter region length and voltage control timing, enabling reduced energy loss during transient On-period while maintaining manageable device complexity through modular structure
Solution Approach 2:
The invention applies preliminary voltage control to the second transistor by applying the second Off-voltage before the first transistor enters transient Off-state, and turning on the second transistor before the first transistor enters transient On-state. This preliminary action prepares the transistors in advance for their respective states, optimizing the switching transitions and reducing energy loss during transient periods
2Loss of energy
If the emitter region length is increased to reduce energy loss, then the transistor performance improves, but the device area increases
Solution Approach 1:
The invention applies different emitter region lengths to different transistors based on their specific functions. The first transistor has a first emitter region length while the second transistor has a second emitter region length that is longer. This local differentiation optimizes each transistor's contribution to reducing energy loss during transient On-period while avoiding the need to increase the emitter region length of all transistors uniformly
Solution Approach 2:
The invention resolves the area constraint by transitioning from a single-transistor design to a multi-transistor configuration. Instead of increasing the emitter region length in one transistor (one-dimensional solution), the invention distributes the functionality across multiple transistors with different emitter region lengths, achieving the same energy loss reduction goal while maintaining compact device area through spatial distribution
Data Source
AI summary
An object is to provide a technique that can reduce energy loss during the transient On-period. A semiconductor device includes a first transistor, a second transistor, and a controller. The controller is configured to, before the first transistor enters a transient Off-state, apply a second Off-voltage lower than a first Off-voltage to the second gate, before the first transistor enters a transient On-state, turn On the second transistor, and after the first transistor is turned On, apply the first Off-voltage to the second gate to turn Off the second transistor.