Memory Chip Judgment Circuit for Stacked Die Mode Detection

Solution Overview

Problem

Memory chips face difficulty in determining whether they are operating as a single die or as part of stacked memory dies due to indistinguishable internal node states when the option pad is floating or tied to different voltage levels, leading to uncertainty in operational mode.

Innovation Solution

A judgment circuit is introduced, comprising a detection unit and a sampling unit coupled to the option pad, which generates a judgment signal based on the option pad's status, using control signals and voltage sources to differentiate between single die, top die, and bottom die modes by varying detection signal levels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the option pad is left floating to indicate single die mode, then the memory chip can operate as a single memory die, but the internal node state becomes indistinguishable from stacked die modes

Engineering Contradiction:

Improveoperational mode flexibilityVSAvoidmode detection accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The judgment circuit performs preliminary detection of the option pad status before the memory chip enters normal operation. By sampling the voltage level at the internal node connected to the option pad during an initialization phase, the system determines the operational mode (single die vs. stacked die) before any ambiguity can arise during normal operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

An intermediate judgment circuit is introduced between the option pad and the rest of the memory chip system. This judgment circuit includes a detection unit that samples the option pad voltage level and a determination unit that translates the sampled voltage into a definitive mode identification, acting as a mediator that resolves the ambiguity between single die and stacked die configurations.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the option pad is tied to voltage sources for stacked die operation, then clear voltage levels are established, but the memory chip cannot distinguish between top die and bottom die roles

Engineering Contradiction:

Improvevoltage level stabilityVSAvoiddie role identification accuracy

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The judgment circuit performs preliminary detection of the option pad status before the memory chip enters normal operation. By sampling the voltage level at the internal node connected to the option pad during an initialization phase, the system determines the operational mode (single die vs. stacked die) before any ambiguity can arise during normal operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

An intermediate judgment circuit is introduced between the option pad and the rest of the memory chip system. This judgment circuit includes a detection unit that samples the option pad voltage level and a determination unit that translates the sampled voltage into a definitive mode identification, acting as a mediator that resolves the ambiguity between single die and stacked die configurations.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If a judgment circuit is added to resolve mode ambiguity, then operational mode can be determined, but device complexity increases

Engineering Contradiction:

Improvemode detection accuracyVSAvoidcircuit structure complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The judgment circuit is segmented into two functional units: a detection unit that samples the option pad voltage level and a determination unit that interprets the sampled voltage to identify the operational mode. This segmentation allows each unit to be optimized for its specific function while keeping the overall circuit manageable in complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The judgment circuit is self-contained and automatically determines the operational mode without requiring external intervention or complex control logic. The detection unit samples the option pad status and the determination unit independently concludes whether the memory chip is operating in single die or stacked die mode, making the system self-identifying.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS8004870B2Memory chips and judgment circuits thereof

Publication Date: 2011.08.23 WINBOND ELECTRONICS CORP

AI summary

A memory chip is provided. The memory chip operates at modes and includes an option pad and a judgment circuit. The judgment circuit is coupled to the option pad generates a judgment signal according to the current status of the option pad. The judgment signal indicates which mode the memory chip is operating at. The judgment circuit includes a detection unit and a sampling unit. The detection unit is coupled to a first voltage source and the option pad and further controlled by a control signal to generate at least one detection signal according to the current status of the option pad. The sampling unit samples the at least one detection signal after the control signal is asserted to generate the judgment signal. When the control signal is asserted, a level of the at least one detection signal is varied by a voltage provided by the first voltage source.