Memory Device CA Signal Parity Checking After Sleep Wake-Up
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Memory devices face transmission errors on the command and address (CA) bus, especially after exiting a sleep mode, due to varying delays in signal paths and clock paths caused by temperature changes, leading to uncertainty about the state to enter and increased latency through CA training.
Innovation Solution
Implementing a memory device with CA samplers and a command decoder to check for parity errors using predetermined patterns in CA signals, allowing for CA bus testing and potentially avoiding direct CA training by ensuring even parity and reducing latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If CA bus operations are performed after exiting sleep mode, then memory device can resume normal operations, but transmission errors may occur due to varying delays in signal paths and clock paths
Solution Approach 1:
The patent applies preliminary action by performing CA training operations before normal CA bus operations resume after sleep mode. The memory device executes training sequences that adjust timing parameters and synchronize signal paths ahead of time, ensuring that when normal operations start, the system is already calibrated and ready, thus preventing transmission errors while enabling quick resumption.
Solution Approach 2:
The patent implements feedback mechanisms where the memory device monitors the quality and timing of CA signals during and after wake-up from sleep mode. Based on this feedback, the system dynamically adjusts timing parameters and re-synchronizes signal paths, ensuring reliable transmission while maintaining high operation resumption speed.
2Reliability
If CA training is performed to ensure accurate signal transmission, then transmission reliability is improved, but access time and latency increase
Solution Approach 1:
The patent applies partial action by performing only the necessary minimum CA training operations required to ensure reliable transmission, rather than comprehensive training sequences. The system identifies and executes only the critical timing adjustments needed after sleep mode, reducing training time while maintaining sufficient transmission accuracy for normal operations.
Solution Approach 2:
The patent implements preliminary anti-action by pre-configuring timing parameters and signal path characteristics before sleep mode enters, and by having ready-to-execute training sequences that can be rapidly deployed upon wake-up. This preparation reduces the actual training time needed after sleep mode by having countermeasures already in place.
3Measurement precision
If the memory device enters an uncertain state after CA transmission errors, then error detection capability is improved, but system state management complexity increases
Solution Approach 1:
The patent applies self-service by implementing automatic error detection and state recovery mechanisms within the memory device. When transmission errors are detected, the system autonomously identifies the erroneous state, executes appropriate correction procedures, and returns to a known good state without requiring complex external intervention or manual state management, thus maintaining simplicity while ensuring accurate error detection.
Data Source
AI summary
A memory device includes: a plurality of command and address (CA) samplers configured to receive, as a plurality of first CA signals, a command comprising a predetermined pattern via a CA bus based on an exit of a sleep mode, wherein each of the plurality of CA samplers further is configured to sample a corresponding first CA signal among the plurality of first CA signals; and a command decoder configured to check a parity error in the plurality of first CA signals sampled by the plurality of CA samplers.