Memory Hold Time Trimming Circuit for SRAM Timing Violations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Timed input and output operations in memory devices, such as SRAM and DRAM, face challenges due to variability in semiconductor manufacturing processes, leading to hold time violations that affect performance and reliability, especially with increasing memory density and shrinking device sizes.
Innovation Solution
A hold time trimming circuit with adjustable delay mechanisms, including switching transistors and decoders, is implemented to precisely control the timing of input signals relative to gating signals, ensuring proper hold time by varying the delay through selective transistor activation and resistor configurations, allowing for manual or automatic adjustment of hold time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If memory device density is increased and device size is shrunk, then productivity and capacity are improved, but manufacturing precision deteriorates leading to hold time violations
Solution Approach 1:
The patent implements a dynamic hold time adjustment mechanism that allows the hold time parameter to be modified after manufacturing. The circuit includes a hold time adjustment circuit that can change the hold time of the gating signal based on detected hold time violations, making the system adaptable to manufacturing variations without requiring precise manufacturing control
Solution Approach 2:
The patent changes the hold time parameter dynamically by adjusting the gating signal characteristics. The hold time adjustment circuit modifies the duration that the gating signal remains active, allowing the system to compensate for manufacturing variations by changing this temporal parameter rather than relying on fixed manufacturing precision
2Reliability
If hold time is adjusted to reduce violations, then reliability is improved, but device complexity increases due to additional trimming circuits
Solution Approach 1:
The patent implements a self-adjusting mechanism where the hold time adjustment circuit automatically detects hold time violations and adjusts the hold time parameter without external intervention. The circuit monitors its own performance and performs self-correction, eliminating the need for complex external testing and adjustment equipment
Solution Approach 2:
The patent incorporates a feedback mechanism where the hold time adjustment circuit detects hold time violations and uses this information to adjust the gating signal hold time. The circuit continuously monitors the timing relationship between input signals and gating signals, creating a closed-loop system that automatically maintains reliable operation
3Ease of operation
If manual or automatic hold time tuning is implemented, then ease of operation is improved, but device complexity increases
Solution Approach 1:
The hold time adjustment circuit operates autonomously by detecting hold time violations and automatically adjusting the hold time parameter. This self-service capability eliminates the need for manual intervention or complex external testing equipment, making the device easier to operate while keeping the adjustment mechanism integrated and relatively simple
Data Source
AI summary
A device for providing gated data signals includes a delay path configured to receive an input signal and output the input signal that is delayed from the input signal by a time interval; a gating signal generator configured to supply a gating signal; a gating circuit configured to receive the data signal from the delay path at the data input, receive the gating signal at the gating input, and output at the data output an output signal indicative of the received data signal when the gating signal is present at the gating input; and a delay controller configured to receive a variable delay control signal and set the delay time interval according to the delay control signal.