Semiconductor Memory Pre-Charge Control for Self-Refresh Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor memory devices face challenges in maintaining stable self-refresh operations due to insufficient active operation time during self-refresh modes, leading to potential data damage and malfunction.
Innovation Solution
The semiconductor memory device employs a pre-charge control system with first and second pre-charge control blocks and an operation control block to generate control signals based on operation clock toggles and active commands, ensuring a minimal active operation section (TRAS_MIN) is maintained during self-refresh operations by disabling and enabling these blocks accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the semiconductor memory device operates in self-refresh mode to save power during standby, then energy consumption is reduced, but the active operation time becomes insufficient leading to unstable refresh operations and potential data damage
Solution Approach 1:
The patent applies preliminary action by pre-calculating and determining the optimal pre-charge timing based on the active operation period before the actual refresh operation occurs. The timing control circuit预先 determines the pre-charge signal generation timing according to the active operation period, ensuring that even with limited active time in self-refresh mode, the refresh operation completes successfully with proper pre-charging, thus maintaining reliability while saving energy.
2Productivity
If the pre-charge operation starts too early after active operation, then the refresh operation can complete faster, but the active operation section becomes insufficient leading to unstable refresh operations
Solution Approach 1:
The patent implements feedback by using the timing control circuit to monitor and adjust pre-charge signal generation based on the actual active operation period. The circuit receives the active command signal and operation clock signal, counts the active operation period, and dynamically determines the pre-charge timing accordingly. This feedback mechanism ensures that the pre-charge operation starts at the optimal time that guarantees sufficient active operation section while maintaining efficient refresh operation speed.
3Loss of energy
If the semiconductor memory device enters standby or power-saving mode for extended periods, then energy savings increase, but the self-refresh operation becomes critical for maintaining data integrity
Solution Approach 1:
The patent applies self-service by enabling the timing control circuit to autonomously manage the self-refresh operation without external intervention. During standby or power-saving modes, the circuit automatically generates the pre-charge signal at the correct timing based on internal counting of operation clock cycles, ensuring data integrity is maintained through proper refresh operations. This self-managed refresh mechanism allows the device to remain in low-power states for extended periods while reliably preserving data.
Data Source
AI summary
A semiconductor memory device includes a first pre-charge control block suitable for generating a first control signal by counting a number of toggles of an operation clock in response to a first active pulse in a self-refresh operation exit mode, a second pre-charge control block suitable for generating a second control signal in response to an active command for an active operation in a self-refresh operation mode, and an operation control block suitable for disabling the first pre-charge control block in the self-refresh operation mode, and disabling the second pre-charge control block in a self-refresh operation exit mode, wherein a pre-charge operation starts in response to the first and second control signals after the active operation. The semiconductor memory device may then be secured in a minimal time for stably performing an active operation during a self-refresh operation.