Voltage Regulator Gate Voltage Control for Switching Loss Reduction

Solution Overview

Problem

Conventional switching voltage regulators face inefficiencies and increased switching times due to fixed gate voltage levels, leading to higher power dissipation and reduced lifespan of oxide layers in low-power devices like laptops and cellular phones.

Innovation Solution

An adjustable DC voltage source is implemented to dynamically adjust the gate voltage of high-side and low-side transistors based on output current measurements, ensuring constant saturation current and reducing switching losses, while also providing discharge protection through a transistor-based switch to prevent kickback and maintain efficient operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If fixed gate voltage levels are used in switching regulators, then device simplicity is maintained, but efficiency decreases and switching times increase

Engineering Contradiction:

Improvegate voltage control circuitVSAvoidpower dissipation

Core Design Contradiction:

Device complexityVSLoss of energy

Solution Approach 1:

The patent implements dynamic gate voltage adjustment by sensing the output current and modulating the gate voltage of the high-side transistor accordingly. The gate voltage transitions from a fixed level to a dynamically adjusted level that varies with load conditions, optimizing the saturation current and reducing switching losses without requiring complex external circuitry

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent employs a feedback mechanism where the output current is sensed and used to adjust the gate voltage of the high-side transistor. This feedback loop ensures that the gate voltage is optimized for each operating condition, maintaining high efficiency across varying load currents while using standard regulator components

Inventive Principle:

Principle #23Feedback

2Device complexity

If fixed gate voltage levels are used in switching regulators, then circuit simplicity is maintained, but switching time increases

Engineering Contradiction:

Improvegate voltage control circuitVSAvoidswitching time

Core Design Contradiction:

Device complexityVSSpeed

Solution Approach 1:

The patent implements dynamic gate voltage adjustment by sensing the output current and modulating the gate voltage of the high-side transistor accordingly. The gate voltage transitions from a fixed level to a dynamically adjusted level that varies with load conditions, optimizing the saturation current and reducing switching losses without requiring complex external circuitry

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the gate voltage parameter dynamically based on output current conditions. By adjusting the gate voltage level according to the sensed current, the saturation current of the high-side transistor is optimized for each operating point, thereby reducing switching time without adding circuit complexity

Inventive Principle:

Principle #35Parameter changes

3Loss of energy

If higher gate voltage is used to increase saturation current, then switching efficiency improves, but oxide layer lifespan decreases

Engineering Contradiction:

Improveswitching lossVSAvoidoxide layer lifespan

Core Design Contradiction:

Loss of energyVSDuration of action of stationary object

Solution Approach 1:

The patent implements dynamic gate voltage adjustment by sensing the output current and modulating the gate voltage of the high-side transistor accordingly. The gate voltage transitions from a fixed level to a dynamically adjusted level that varies with load conditions, optimizing the saturation current and reducing switching losses without requiring complex external circuitry

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the gate voltage parameter dynamically based on output current conditions. By adjusting the gate voltage level according to the sensed current, the saturation current of the high-side transistor is optimized for each operating point, thereby reducing switching time without adding circuit complexity

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS9178408B2Voltage regulators with load-dependent bias

Publication Date: 2015.11.03 VOLTERRA SEMICONDUCTOR CORPORATION

AI summary

This document describes systems and techniques related to voltage regulators. The subject matter of this document can be embodied in a method that includes measuring an output current of a switching regulator. The switching regulator includes a high-side transistor and a low side-transistor wherein the high-side transistor and the low-side transistor are driven using a first gate voltage and a second, different gate voltage, respectively. The method also includes adjusting a direct-current (DC) voltage source of the switching regulator such that the first gate voltage is adjusted in accordance with the measured output current.