Semiconductor Gate Driving Method for Miller Period Noise Control

Solution Overview

Problem

Existing semiconductor device driving methods face a trade-off between reducing switching loss and electromagnetic noise, with current techniques either increasing power loss or failing to adequately reduce noise, especially during turn-on operations.

Innovation Solution

A semiconductor device driving method that adjusts the gate driving ability during a Miller period, reducing it at a first time point and increasing it at a second time point, to minimize electromagnetic noise without increasing power loss, using a driving circuit with an adjusting unit to control the gate voltage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the gate charging/discharging speed is increased to reduce switching loss, then the switching loss is reduced, but the electromagnetic noise increases

Engineering Contradiction:

Improveswitching lossVSAvoidelectromagnetic noise

Core Design Contradiction:

Loss of energyVSObject-generated harmful factors

Solution Approach 1:

The patent applies dynamics by making the gate charging/discharging speed variable rather than constant. The driving ability is dynamically adjusted during the Miller period - reduced at a first time point and increased at a second time point - to optimize both switching loss and electromagnetic noise at different stages of the switching process

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies periodic action by dividing the Miller period into distinct phases with different driving abilities. The driving ability is periodically modified during the Miller period, creating a structured temporal pattern of high and low driving ability phases to balance switching performance and noise reduction

Inventive Principle:

Principle #19Periodic action

2Object-generated harmful factors

If the gate charging/discharging speed is decreased to reduce electromagnetic noise, then the electromagnetic noise is reduced, but the switching loss increases

Engineering Contradiction:

Improveelectromagnetic noiseVSAvoidswitching loss

Core Design Contradiction:

Object-generated harmful factorsVSLoss of energy

Solution Approach 1:

The patent applies dynamics by making the gate charging/discharging speed variable rather than constant. The driving ability is dynamically adjusted during the Miller period - reduced at a first time point and increased at a second time point - to optimize both switching loss and electromagnetic noise at different stages of the switching process

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies periodic action by dividing the Miller period into distinct phases with different driving abilities. The driving ability is periodically modified during the Miller period, creating a structured temporal pattern of high and low driving ability phases to balance switching performance and noise reduction

Inventive Principle:

Principle #19Periodic action

3Object-generated harmful factors

If the driving ability is kept low from the time it is reduced to the completion of switching to reduce electromagnetic noise, then the electromagnetic noise is reduced, but the switching time increases which may increase switching loss

Engineering Contradiction:

Improveelectromagnetic noiseVSAvoidswitching time

Core Design Contradiction:

Object-generated harmful factorsVSLoss of time

Solution Approach 1:

The patent applies periodic action by dividing the Miller period into distinct phases with different driving abilities. The driving ability is periodically modified during the Miller period, creating a structured temporal pattern of high and low driving ability phases to balance switching performance and noise reduction

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The patent applies dynamics by making the gate charging/discharging speed variable rather than constant. The driving ability is dynamically adjusted during the Miller period - reduced at a first time point and increased at a second time point - to optimize both switching loss and electromagnetic noise at different stages of the switching process

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS10749519B2Semiconductor device driving method and driving apparatus and power conversion apparatus

Publication Date: 2020.08.18 MITSUBISHI ELECTRIC CORP

AI summary

Turn-on and turn-off of a semiconductor device are controlled through control of a gate voltage in accordance with a driving control signal. At a first time after a start of a Miller period of a gate voltage in driving a gate of the semiconductor device in accordance with the driving control signal, a driving signal is changed from “1” to “0” to thereby make a gate driving ability temporarily lower than the gate driving ability during a period from a starting time of the turn-on operation to the first time. Further, at a second time corresponding to an end of the Miller period, the driving signal is changed from “0” to “1” to thereby increase the gate driving ability.