Shared-Clock Multi-Bit Flip-Flops for Lower VLSI Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional flip-flop circuits in VLSI systems have a high power consumption due to a large number of clock-activated transistors, which burdens the clock network and increases power consumption, leading to voltage drops and internal node toggling issues.
Innovation Solution
A compound sequential circuit architecture that shares clock-activated transistors across multiple flip-flops, reducing the number of clock-activated transistors per flip-flop and utilizing shared clock nodes to minimize transistor load on the clock network, thereby reducing power consumption and avoiding contentions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional flip-flop circuits use individual clock-activated transistors for each flip-flop, then each flip-flop can operate independently, but the total number of clock-activated transistors increases, leading to high power consumption and voltage drops
Solution Approach 1:
Multiple flip-flops share common clock-activated transistors and clock nodes instead of each having dedicated transistors. The patent shows flip-flops FF0-FF3 sharing clock nodes CLK0, CLK1, CLK2 through common clock-activated transistors, reducing total transistor count while maintaining independent data path operation for each flip-flop
Solution Approach 2:
Clock-activated transistors serve multiple flip-flops simultaneously rather than being dedicated to single units. The shared clock nodes and transistors provide universal clocking functionality across multiple sequential elements, reducing overall circuit complexity and power consumption
2Use of energy by moving object
If the number of clock-activated transistors is reduced through sharing, then power consumption decreases, but circuit complexity increases due to shared resources
Solution Approach 1:
The clock network is segmented into distinct clock nodes (CLK0, CLK1, CLK2) that can be independently controlled and timed. Each segment serves specific groups of flip-flops, allowing granular power management and reduced contention while maintaining modularity in the shared architecture
Solution Approach 2:
Clock nodes act as intermediary elements between the clock source and individual flip-flops. These intermediate nodes buffer and distribute clock signals, managing the shared resources efficiently while isolating individual flip-flop operations and reducing direct contention
3Speed
If more clock-activated transistors are used, then better clock signal distribution is achieved, but voltage drops and internal node toggling issues increase
Solution Approach 1:
Instead of providing full dedicated clocking infrastructure to each flip-flop, the system uses partial sharing where multiple flip-flops share common clock-activated transistors and nodes. This reduces the excessive transistor count while maintaining sufficient clock signal distribution through the shared elements
4Reliability
If individual clocking resources are allocated to each flip-flop, then clock signal integrity is maintained, but transistor load on the clock network increases
Solution Approach 1:
The patent discards the conventional approach of dedicating separate clock-activated transistors to each flip-flop. Instead, it recovers resources by having multiple flip-flops share common clock-activated transistors and clock nodes, reducing total transistor load while maintaining clock signal integrity through proper timing and buffering
Data Source
AI summary
Circuits, methods, and systems for generating data outputs based on sampled data inputs. One circuit includes a first clock-activated transistor electrically coupled to a first shared clock node, a second clock-activated transistor coupled to a second shared clock node, a third clock-activated transistor coupled to a third shared clock node, a plurality of flip-flops, a latch electrically coupled to the second shared clock node and the third shared clock node, and a first keeper sub-circuit electrically coupled to the third shared clock node and at least one of a first output or a second output of the latch. Each flip-flop of the plurality of flip-flops includes a latch electrically coupled to the second shared clock node and the third shared clock node and a first keeper sub-circuit electrically coupled to the third shared clock node and at least one of a first output or a second output of the latch.