Semiconductor Memory Repair Address Signal Multiplexing

Solution Overview

Problem

Conventional semiconductor memory devices face challenges in efficiently transferring address signals as the number of banks increases, leading to reduced integration density and increased size due to the need for numerous transmission lines for redundancy address signals, which are specific to each bank and require more lines than normal address signals.

Innovation Solution

A semiconductor memory device design that includes a repair address generation unit, a line choice address generation unit, and a cell line decoding unit to selectively drive local cell lines in either normal or redundancy cell regions based on whether a repair address signal is used, combining normal and repair address signals to minimize the number of transmission lines needed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate transmission lines are provided for each bank to transfer repair address signals, then each bank can independently receive repair address signals, but the number of transmission lines increases significantly, reducing integration density and increasing device size

Engineering Contradiction:

Improveindependent repair address signal transferVSAvoiddevice size

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent merges the transfer of normal address signals and repair address signals into a single transmission line by time-division multiplexing. The repair address generation unit generates repair address signals that are combined with normal address signals and transmitted together through the same line to the cell line decoding units, eliminating the need for separate transmission lines for each bank.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The transmission lines are designed to serve multiple functions: they can transfer both normal address signals and repair address signals depending on the operational mode. The cell line decoding units are configured to receive and process both types of signals through the same transmission infrastructure, making the system more versatile and reducing overall line count.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If separate transmission lines are provided for each bank to transfer repair address signals, then each bank can independently receive repair address signals, but the number of transmission lines increases significantly, reducing integration density

Engineering Contradiction:

Improveindependent repair address signal transferVSAvoidintegration density

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the transfer of normal address signals and repair address signals into a single transmission line by time-division multiplexing. The repair address generation unit generates repair address signals that are combined with normal address signals and transmitted together through the same line to the cell line decoding units, eliminating the need for separate transmission lines for each bank.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The system dynamically switches between normal address signal mode and repair address signal mode using control signals. The cell line decoding units can dynamically select whether to process normal address signals or repair address signals based on the state of repair address use judgment signals, allowing flexible adaptation without requiring separate static transmission lines.

Inventive Principle:

Principle #15Dynamics

3Productivity

If more transmission lines are used to transfer repair address signals to multiple banks, then address signal transfer efficiency is maintained, but power consumption increases

Engineering Contradiction:

Improveaddress signal transfer efficiencyVSAvoidpower consumption

Core Design Contradiction:

ProductivityVSUse of energy by stationary object

Solution Approach 1:

The patent merges the transfer of normal address signals and repair address signals into a single transmission line by time-division multiplexing. The repair address generation unit generates repair address signals that are combined with normal address signals and transmitted together through the same line to the cell line decoding units, eliminating the need for separate transmission lines for each bank.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The system uses periodic time-division multiplexing to alternate between transmitting normal address signals and repair address signals on the same transmission lines. Control signals periodically enable or disable the transfer of repair address signals based on whether repair operations are needed, optimizing power consumption by activating repair signal transfer only when necessary.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS8331174B2Semiconductor memory device and method for operating the same

Publication Date: 2012.12.11 SK HYNIX INC

AI summary

A semiconductor memory device includes: a repair address generation unit configured to generate a repair address signal in response to a first address signal; a line choice address generation unit configured to generate a line choice address signal by combining the first address signal and the repair address signal according to a determination as to whether the repair address signal is to be used; and a cell line decoding unit configured to select one of a normal cell region and a redundancy cell region according to the determination, and select one of a plurality of local cell lines provided in the selected cell region in response to the line choice address signal.