Bimodal Source-Synchronous Interface With Delay-Chain Phase Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Source synchronous interfaces face limitations due to uncertainty caused by process, voltage, and temperature variations, which limits the highest frequency at which they can operate, especially in applications where the source and receiver clocks have a phase mismatch, making it impractical to employ faster devices without adding significant circuitry like FIFOs or DLLs/PLLs.
Innovation Solution
A source synchronous interface is configured with configurable logic to include delay chains and register blocks for both clock and data signals, allowing for adjustable delays to achieve phase alignment, enabling operation in multiple modalities and improving flexibility without excessive circuitry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a FIFO or DLL/PLL is added to account for phase mismatch, then phase alignment and reliability are improved, but device complexity and circuitry increase significantly
Solution Approach 1:
The patent extracts the phase adjustment functionality from complex external circuits (FIFO, DLL, PLL) and implements it directly within the receiver using simple delay elements controlled by a phase adjustment unit. This removes the need for additional complex circuitry while maintaining phase alignment capability.
Solution Approach 2:
The receiver is designed to self-adjust its phase alignment by using the forwarded clock signal itself to control delay elements. The system automatically compensates for phase mismatch without requiring external complex circuitry or additional synchronization components.
2Speed
If faster devices are employed to increase operational frequency, then speed is improved, but uncertainty due to process, voltage, and temperature variations increases, limiting reliability
Solution Approach 1:
The patent dynamically adjusts delay parameters based on operating conditions by using the forwarded clock signal to control delay elements. This allows the system to adapt to process, voltage, and temperature variations, maintaining reliable operation at higher frequencies where such variations have greater impact.
3Reliability
If tailored printed circuit board trace lengths are used to avoid phase mismatch, then phase alignment is improved, but adaptability to environmental changes or operational modifications is reduced
Solution Approach 1:
The patent implements dynamic phase adjustment using controllable delay elements that can be modified in real-time based on operating conditions. Unlike fixed trace lengths, this dynamic approach allows the system to adapt to environmental changes or operational modifications while maintaining phase alignment.
Data Source
AI summary
Method and apparatus for a bimodal source synchronous interface for a receiver module is described. A first input cell with a first delay chain and a first register block is provided for receipt of a forwarded clock signal by the first delay chain. A second input cell with a second delay chain and a second register block is provided for receipt of a data signal by the second delay chain. The second input cell is configured such that output from the second delay chain is coupled to a data input of the second register block. The first input cell and the second input cell may be operated in either a first modality or a second modality. The first modality may be for interfacing to a synchronous integrated circuit interface. The second modality may be for interfacing to a synchronous network/telecommunications interface.