Clock Delay Control Using Phase Interpolation Against Supply Ripple
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As integrated circuits become more complex, mismatches in clock signal arrival times due to fluctuations in supply voltage cause timing issues and limit operational speed, as the delay introduced by clock distribution buffers is sensitive to voltage changes, necessitating a reduction in supply voltage level dependency on clock distribution network propagation delay.
Innovation Solution
A clock delay control circuit comprising a sensing circuit and a phase interpolator, where the sensing circuit generates control signals to adjust the coupling between multiple paths with different propagation delays, allowing the phase interpolator to compensate for changes in supply voltage, thereby stabilizing the clock signal delay.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If buffers or amplifiers are used in the clock distribution network, then the clock signal can be buffered and distributed throughout the integrated circuit, but the propagation delay becomes sensitive to supply voltage fluctuations causing timing mismatches
Solution Approach 1:
The patent implements dynamic adjustment of buffer propagation delay by sensing supply voltage fluctuations and controlling the buffers to compensate for delay variations. The system transitions from static buffer behavior to dynamic adaptation, adjusting the propagation delay in real-time based on voltage conditions to maintain timing accuracy across different operating scenarios.
2Productivity
If the integrated circuit is operated at higher speed or frequency, then productivity increases, but timing mismatches in clock distribution become more critical and may cause incorrect operation
Solution Approach 1:
The patent employs a feedback mechanism where the propagation delay of clock signals is sensed and used to control the buffers. This closed-loop system continuously monitors timing delays and adjusts buffer behavior accordingly, enabling the clock distribution network to maintain synchronization even at higher operational speeds where timing margins are reduced.
3Reliability
If supply voltage level is reduced to decrease buffer delay sensitivity, then timing accuracy improves, but the power supply must be designed to maintain stable voltage levels
Solution Approach 1:
The patent implements a self-regulating system where the buffer propagation delay automatically adjusts in response to supply voltage fluctuations without requiring external intervention. The sensing mechanism detects voltage changes and the buffers self-correct their delay characteristics, eliminating the need for complex external voltage regulation circuitry while maintaining timing stability.
Data Source
AI summary
Embodiments relate to a circuit implementation for controlling a delay of a clock signal. The clock delay control circuit includes a sensing circuit and a phase interpolator controlled by the sensing circuit. The sensing circuit generates a first control signal that increases when a level of a supply voltage increases, and decreases when the level of the supply voltage decreases. Moreover, the sensing circuit generates a second control signal that decreases when the level of the supply voltage increases, and increases when the level of the supply voltage decreases. The phase interpolator includes multiple paths, each having a different propagation delay. The coupling between each path and the output node of the phase interpolator is controlled by the control signals generated by the sensing circuit.