Memory Interface Output Driver Switching for Noise and Impedance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increased operation speed of data transmission between a system on chip (SoC) and a memory device leads to increased external noise and impedance mismatching in input/output interfaces, which existing technologies struggle to address effectively.
Innovation Solution
A method of operating an input/output interface that selects and uses appropriate output driver circuits and input receiver circuits based on a mode selection signal, which is generated based on memory latency and a mode register set command, to adjust operation frequency and select termination levels, thereby controlling on-die termination circuits to mitigate impedance mismatching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If operation speed is increased, then data transmission efficiency is improved, but external noise and impedance mismatching increase
Solution Approach 1:
The patent implements dynamic selection of output driver circuits and on-die termination circuits based on operating conditions. The system switches between different driver circuits (e.g., first output driver circuit with weaker drive strength, second output driver circuit with stronger drive strength) and different termination configurations to adapt to varying data rates and impedance requirements, thereby maintaining signal quality across different speeds
Solution Approach 2:
The patent changes physical parameters of the output driver circuits by providing multiple circuits with different drive strengths and characteristics. By selecting appropriate circuits based on operating mode, the system adjusts parameters like drive strength and termination resistance to optimize performance at different data rates while minimizing noise and impedance issues
2Adaptability or versatility
If multiple output driver circuits are provided for different operation modes, then adaptability to varying speeds is improved, but device complexity increases
Solution Approach 1:
The patent segments the output driver functionality into multiple independent driver circuits, each optimized for specific operating modes. This segmentation allows independent optimization of each circuit for its intended speed range while using selection logic to activate only the appropriate circuit, managing complexity through functional separation
Solution Approach 2:
The patent creates multi-functional output driver circuits that can operate across different data rates and modes. By designing circuits with adjustable characteristics and multiple termination options, a single circuit can serve multiple functions across different operating conditions, reducing the need for completely separate dedicated circuits
Data Source
AI summary
A method of operating an input/output interface includes selecting one of a plurality of output driver circuits according to a mode selection signal, and outputting a data signal using the selected one of the plurality of output driver circuits. Another method of operating an includes generating a mode selection signal based on a received command signal, and controlling an on-die termination (ODT) circuit included in the input/output interface according to the mode selection signal. Another method of operating an includes generating a mode selection signal based on a received command signal, and controlling an ODT circuit included in the input/output interface according to the mode selection signal.