Output Driver Switching Between PMOS and NMOS Transistors

Solution Overview

Problem

Memory devices face challenges in efficiently operating at varying supply voltages, particularly in low-power applications where PMOS transistors are not feasible, leading to reduced signal integrity.

Innovation Solution

An output driver configuration that includes a main driver with PMOS and NMOS transistors, a pre-driver, and a switching unit, allowing the output node to be coupled to either a high or low supply voltage based on mode of operation, using control signals to switch between PMOS/NMOS configurations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If PMOS transistors are used in output driver for high supply voltage operation, then signal integrity is improved, but device complexity and power consumption increase making it infeasible for low-power applications

Engineering Contradiction:

Improvesignal integrityVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The output driver dynamically switches between PMOS and NMOS transistor configurations based on operating conditions. A switching unit controlled by a control signal selects which transistor type connects the output node to the supply voltage, allowing the device to adapt its structure between high-voltage/high-integrity mode (PMOS) and low-power mode (NMOS), thereby resolving the contradiction between signal integrity and device complexity

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the electrical parameters of the output driver by switching between different transistor types (PMOS with higher threshold voltage for noise immunity vs. NMOS with lower threshold voltage for lower power consumption). This parameter change allows the system to optimize signal integrity when needed while reducing complexity and power consumption in low-power applications

Inventive Principle:

Principle #35Parameter changes

2Reliability

If PMOS transistors are used in output driver, then signal integrity is improved, but power consumption increases

Engineering Contradiction:

Improvesignal integrityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The output driver dynamically switches between PMOS and NMOS transistor configurations based on operating conditions. A switching unit controlled by a control signal selects which transistor type connects the output node to the supply voltage, allowing the device to adapt its structure between high-voltage/high-integrity mode (PMOS) and low-power mode (NMOS), thereby resolving the contradiction between signal integrity and device complexity

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the electrical parameters of the output driver by switching between different transistor types (PMOS with higher threshold voltage for noise immunity vs. NMOS with lower threshold voltage for lower power consumption). This parameter change allows the system to optimize signal integrity when needed while reducing complexity and power consumption in low-power applications

Inventive Principle:

Principle #35Parameter changes

3Use of energy by moving object

If output driver operates at low supply voltage, then power consumption is reduced, but signal integrity deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoidsignal integrity

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The output driver dynamically switches between PMOS and NMOS transistor configurations based on operating conditions. A switching unit controlled by a control signal selects which transistor type connects the output node to the supply voltage, allowing the device to adapt its structure between high-voltage/high-integrity mode (PMOS) and low-power mode (NMOS), thereby resolving the contradiction between signal integrity and device complexity

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the electrical parameters of the output driver by switching between different transistor types (PMOS with higher threshold voltage for noise immunity vs. NMOS with lower threshold voltage for lower power consumption). This parameter change allows the system to optimize signal integrity when needed while reducing complexity and power consumption in low-power applications

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS10902907B1Output drivers, and related methods, memory devices, and systems

Publication Date: 2021.01.26 MICRON TECHNOLOGY INC

AI summary

An output driver is disclosed. An output driver may include a pre-driver and a main driver coupled to the pre-driver. The main driver may include at least one switch, and a first transistor coupled between a first supply voltage and the at least one switch. The main driver may also include a second transistor coupled between a second, different supply voltage and the at least one switch. The at least one switch is configured to couple an output node of the output driver to one of the first transistor and the second transistor in response to receipt of a control signal. The main driver may also include a third transistor coupled between a reference voltage and the output node. An electronic system including at least one output driver, and methods of operating an output driver are also described.