Switching Control Circuit for MOSFET Gate Timing Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-breakdown voltage MOSFET driving circuits for large motors, controlling the derivative values of drain voltage or current is challenging due to signal delay, which affects noise and loss trade-offs.
Innovation Solution
A switching control circuit with a difference detection unit and gate adjustment circuitry that optimizes the timing and amplitude of the gate signal by detecting differences in derivative values of the drain-source voltage, adjusting the gate signal to minimize differences and match derivative values with target values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the transition time of drain voltage or current is shortened to decrease loss, then noise is increased
Solution Approach 1:
The patent changes the timing parameter of the gate signal (adding a delay component) to optimize the transition characteristics of drain voltage and current. By adjusting the timing at which the gate signal is applied, the derivative values of drain voltage and current are controlled to constant levels, thereby simultaneously managing both loss and noise performance.
2Manufacturing precision
If the gate signal timing is adjusted to control derivative values constantly, then signal delay affects control accuracy
Solution Approach 1:
The patent applies preliminary action by pre-calculating and pre-setting the delay amount based on the relationship between signal delay and derivative values. The delay amount is determined in advance through simulation or measurement, and this pre-determined delay is then applied to the gate signal timing to compensate for the inherent signal delay in the driving circuit, thereby achieving accurate derivative value control despite the delay.
Data Source
AI summary
A switching control circuit has a detector to detect a difference between a control object signal of a switching element to drive a load and a target signal of the control object signal, and gate adjustment circuitry to search for the timing at which the difference becomes the smallest by sweeping timing of adjustment of a gate signal of the switching element.