Memory System Point-to-Point Command Address Bus Relay
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing memory systems face challenges in efficiently communicating command and address information to multiple memory devices while maintaining high performance and reducing signal line requirements.
Innovation Solution
The system employs a point-to-point configuration with integrated circuit devices, including memory devices and a memory controller, where command and address signals are relayed through a C/A bus, and clock signals are regenerated and relayed, using package-on-package technology and wire bonding for efficient signaling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a shared bus configuration is used to communicate command and address information to multiple memory devices, then the system can support multiple devices, but the signal line requirements increase and performance decreases due to signal degradation and timing issues
Solution Approach 1:
The system segments the memory device interface into multiple point-to-point channels, where each memory device has its own dedicated command/address signal path from the memory controller. This eliminates the need for a shared bus and reduces signal line complexity while supporting multiple devices through parallel independent connections.
2Stability of the object's composition
If clock signals are transmitted across multiple memory devices in a daisy-chain configuration, then device synchronization is achieved, but signal degradation and timing skew increase with each relay point
Solution Approach 1:
The memory controller pre-calculates and applies compensation values for propagation delay and timing skew before clock signals are transmitted to memory devices. This preliminary timing adjustment ensures that clock edges arrive at each device at the correct relative times, compensating for the cumulative delay through the daisy-chain configuration.
3Volume of moving object
If package-on-package technology is used to integrate memory devices, then space efficiency and signal routing are improved, but manufacturing complexity increases
Solution Approach 1:
The system uses an intermediary controller package that interfaces between the memory devices and the external system. This intermediary handles the complex signal routing and timing compensation, simplifying the manufacturing process by separating the integration complexity from the memory device fabrication itself.
Data Source
AI summary
Memory devices and a memory controller that controls such memory devices. Multiple memory devices receive commands and addresses on a command/address (C/A) bus that is relayed point-to-point by each memory device. Data is received and sent from these devices to/from a memory controller in a point-to-point configuration by adjusting the width of each individual data bus coupled between the individual memory devices and the memory controller. Along with the C/A bus are clock signals that are regenerated by each memory device and relayed. The memory controller and memory devices may be packaged on a single substrate using package-on-package technology. Using package-on-package technology allows the relayed C/A signals to connect from memory device to memory device using wire bonding. Wirebond connections provide a short, high-performance signaling environment for the chip-to-chip relaying of the C/A signals and clocks from one memory device to the next in the daisy-chain.