Input Output Circuit Skew Control via Delay Code Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing input/output circuits in memory systems face challenges in reducing read operation time and improving data reliability due to skew issues between data and strobe signals, which affect data transfer efficiency.
Innovation Solution
An input/output circuit is designed with a data buffer group, digitally controlled delay line, sampler, and de-skew circuit to buffer and delay data and strobe signals, reducing skew by generating and controlling delay codes, thereby improving data transfer reliability and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If data and strobe signals are transmitted through separate paths, then data transfer speed is improved, but skew between rising and falling data increases
Solution Approach 1:
The de-skew circuit uses feedback from sampled data to detect skew between rising and falling data, then generates delay codes to adjust the delay time of the data path and data strobe path, creating a closed-loop control system that automatically compensates for skew
Solution Approach 2:
The invention dynamically changes the delay parameter of the data path and data strobe path based on detected skew conditions, adjusting the delay time to minimize skew between rising and falling data while maintaining high data transfer speed
2Reliability
If delay time is increased to reduce skew, then data transfer reliability is improved, but read operation time increases
Solution Approach 1:
The invention dynamically adjusts the delay time of the data path and data strobe path based on real-time skew detection, rather than using a fixed delay, allowing the system to minimize delay while maintaining reliability by only applying necessary delay compensation
3Reliability
If skew between data and strobe signals is reduced, then data transfer reliability is improved, but circuit complexity increases
Solution Approach 1:
The de-skew circuit performs multiple functions: it samples data, detects skew between rising and falling data, generates delay codes, and controls delay time, consolidating these functions into a single integrated circuit rather than separate components
Data Source
AI summary
An input/output circuit includes a data buffer group configured to buffer data received through data lines, a data strobe buffer configured to buffer a data strobe signal to output a buffered data strobe clock, a digitally controlled delay line configured to output delay data by controlling skew of the buffered data according to a delay code, a data strobe clock output circuit configured to generate a delay data strobe clock in response to the buffered data strobe clock, a sampler configured to sample the delay data according to the delay data strobe clock to output sampled data, and a de-skew circuit configured to update the delay code according to the sampled data.