Semiconductor Memory Power Switch Layout for Standby Leakage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor memory devices experience leakage current and latch-up issues when power voltage is interrupted in standby mode, causing the input node to float and making it difficult to confirm the internal voltage, leading to unnecessary current consumption and operational limitations in mobile devices.
Innovation Solution
A semiconductor memory device is designed with a first power switch to interrupt the power voltage supply and a second power switch connected between the first node and a second node applied with a second power voltage, ensuring the input node is not floated by applying a predetermined voltage, thereby preventing leakage current and latch-up through various configurations, including resistor devices and NMOS transistors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the power voltage VDD is interrupted through the power switch in standby mode, then current consumption is reduced, but leakage current is generated and latch-up occurs
Solution Approach 1:
A second power switch is introduced as an intermediary component between the first power switch and the internal circuit. This second power switch remains in the ON state during standby mode, providing a continuous power path that prevents the input node from floating, thereby eliminating leakage current and latch-up while the first power switch interrupts the main power supply to reduce current consumption.
2Use of energy by moving object
If the power voltage VDD is interrupted in standby mode, then current consumption is reduced, but the input node floats and voltage cannot be confirmed
Solution Approach 1:
The second power switch serves as a mediator that maintains the input node's voltage state by providing a continuous power connection. This allows the voltage at the input node to be confirmed and maintained at a valid logic level even when the main power supply is interrupted by the first power switch, thus solving both the voltage confirmation issue and preventing leakage current.
3Use of energy by moving object
If a single power switch is used to interrupt power supply in standby mode, then current consumption is reduced, but device complexity increases due to additional power switches
Solution Approach 1:
The power switching function is segmented into two distinct power switches with different functions. The first power switch handles the main power supply interruption for current reduction, while the second power switch maintains the power path for voltage stability. This segmentation allows each switch to be optimized for its specific function, reducing overall system complexity despite adding one more component.
Data Source
AI summary
A semiconductor memory device includes a first power switch for interrupting supply of a first power voltage to a first node in a standby mode, and a second power switch connected between the first node and a second node applied with a second power voltage.