Critical Path Delay Adjustment Using Variable Supply-Controlled Inverters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated circuits face manufacturing variations and aging issues that cause critical path delays to deviate from acceptable ranges, leading to reduced yield and incorrect operation.
Innovation Solution
Incorporating variable delay circuitry in critical path circuits, controlled by path control circuitry, to adjust path delays and match target delays, reducing variations due to manufacturing and aging effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If critical path circuits are designed with fixed delay, then manufacturing process is simple, but path delay variations due to manufacturing variability and aging cause incorrect operation and reduced yield
Solution Approach 1:
The patent applies dynamics by transforming the fixed delay circuit into a variable delay circuit. The critical path circuit includes a variable delay element that can dynamically adjust its delay value based on detected path delay measurements. This allows the circuit to adapt to manufacturing variations and aging effects, ensuring correct operation while maintaining a relatively simple overall structure.
Solution Approach 2:
The patent implements feedback by measuring the actual path delay of the critical path circuit and using this measurement to control the variable delay element. The path delay measurement unit detects the current delay, and this information feeds back to adjust the delay element accordingly, creating a closed-loop system that compensates for variations and maintains reliable operation.
2Manufacturing precision
If variable delay circuitry is added to adjust path delays, then manufacturing yield increases, but device complexity and area increase
Solution Approach 1:
The patent uses a variable delay element that can be dynamically adjusted to match target path delays. This dynamic adjustment capability allows the circuit to compensate for manufacturing variations, achieving precise path delay matching while adding minimal structural complexity compared to fully static designs.
Solution Approach 2:
The critical path circuit performs self-adjustment by measuring its own path delay and automatically controlling its variable delay element to match the target delay. This self-service mechanism reduces the need for external calibration and complex control systems, achieving precise delay matching with relatively simple added circuitry.
3Productivity
If critical paths operate at maximum speed, then processing performance is maximized, but path delay variations cause timing violations and incorrect operation
Solution Approach 1:
The patent enables dynamic adjustment of the critical path delay to optimize both speed and reliability. The variable delay element can be tuned to achieve the minimum required delay for maximum processing speed while ensuring the path delay remains within acceptable timing margins, adapting to variations in real-time.
Solution Approach 2:
The path delay measurement and control mechanism provides feedback to maintain timing accuracy. By continuously monitoring the actual path delay and adjusting the variable delay element, the system ensures that critical paths operate at maximum speed without violating timing constraints, even in the presence of manufacturing and aging variations.
4Speed
If path delay is reduced for faster operation, then processing speed increases, but minimum path delay requirements may not be met causing incorrect operation
Solution Approach 1:
The variable delay element provides dynamic control over the critical path delay, allowing the circuit to operate at the minimum acceptable delay for maximum speed while ensuring compliance with minimum delay requirements. The delay can be adjusted based on actual measurements to maintain reliability.
Solution Approach 2:
The feedback mechanism measures the actual path delay and compares it against target values, automatically adjusting the variable delay element to ensure minimum delay requirements are met. This allows the circuit to operate as fast as possible while maintaining correct operation.
Data Source
AI summary
An integrated circuit includes processing circuitry that includes a plurality of critical path circuits. These critical path circuits include variable delay circuits which add an additional delay in to a path delay through each of the critical path circuits so as to adjust the path delay to match a target path delay. Variable delay circuit includes a tank capacitor which is charged or discharged to generate a control voltage. This control voltage serves to control a power supply voltage fed to an inverter chain. Variation in the power supply voltage of the inverter chain adjust the propagation speed of a processing signal through the inverter chain and accordingly adjusts the additional delay imposed by the variable delay circuit.