Word Line Driver Standby Voltage Control

Solution Overview

Problem

Word line drivers in semiconductor memory systems experience significant gate-induced diode leakage (GIDL) currents during standby mode, leading to substantial unwanted power consumption due to the coupling of pFET and nFET gates, which are not effectively addressed by conventional methods.

Innovation Solution

The implementation of a phase decoder that provides a non-zero voltage phase signal less than VCCP to the source of the pFET, reducing the gate-to-source voltage and thereby minimizing GIDL currents, while using a standby PH circuit to couple the word line to a VCC voltage during standby mode, reducing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the gates of pFET and nFET are coupled together in the word line driver, then the word line can be quickly activated and deactivated, but gate-induced diode leakage (GIDL) current occurs during standby mode, causing substantial unwanted power consumption

Engineering Contradiction:

Improveword line activation and deactivation speedVSAvoidpower consumption during standby mode

Core Design Contradiction:

SpeedVSLoss of energy

Solution Approach 1:

The patent segments the gate control by introducing a separate control mechanism for the pFET gate. During standby mode, the pFET gate is controlled independently from the nFET gate, allowing it to be held at a specific voltage level that prevents GIDL current while maintaining the ability for quick activation when needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent changes the voltage parameter of the pFET gate during standby mode. By holding the pFET gate at a voltage level that is not equal to the source voltage (avoiding zero gate-to-source voltage difference), the patent prevents GIDL current while preserving the transistor's ability to switch quickly when activated.

Inventive Principle:

Principle #35Parameter changes

2Loss of energy

If ground voltage is provided to the phase signal during standby mode, then power consumption is reduced, but GIDL current increases due to significant gate-to-source voltage on pFET

Engineering Contradiction:

Improvepower consumption during standby modeVSAvoidGIDL current

Core Design Contradiction:

Loss of energyVSObject-generated harmful factors

Solution Approach 1:

The patent changes the voltage parameter of the pFET gate during standby mode. By holding the pFET gate at a voltage level that is not equal to the source voltage (avoiding zero gate-to-source voltage difference), the patent prevents GIDL current while preserving the transistor's ability to switch quickly when activated.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary control mechanism that manages the pFET gate voltage separately from the nFET gate control. This intermediary control ensures that during standby mode, the pFET gate is held at an appropriate voltage level to prevent GIDL current, while still allowing quick activation when needed.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Power

If VCCP voltage is provided to the gate of pFET to activate the word line, then the word line can be pulled up to VCCP, but GIDL current occurs when ground is provided to the phase signal during standby

Engineering Contradiction:

Improveword line voltage levelVSAvoidpower consumption during standby mode

Core Design Contradiction:

PowerVSLoss of energy

Solution Approach 1:

The patent segments the gate control by introducing a separate control mechanism for the pFET gate. During standby mode, the pFET gate is controlled independently from the nFET gate, allowing it to be held at a specific voltage level that prevents GIDL current while maintaining the ability for quick activation when needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent changes the voltage parameter of the pFET gate during standby mode. By holding the pFET gate at a voltage level that is not equal to the source voltage (avoiding zero gate-to-source voltage difference), the patent prevents GIDL current while preserving the transistor's ability to switch quickly when activated.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS9299406B2Apparatuses and methods for providing word line voltages during standby

Publication Date: 2016.03.29 MICRON TECHNOLOGY INC

AI summary

Apparatuses and methods of providing word line voltages include an example apparatus including a voltage driver and a word line driver. The voltage driver is configured to provide a word line voltage, wherein the word line voltage is a pumped supply voltage responsive to an active mode and the word line voltage is a non-zero voltage less than the pumped supply voltage during a standby mode. The word line driver is coupled to the voltage driver and is configured to drive a respective word line to the word line voltage during the active and standby modes.