I/O Level Shifter Control for Stable Output Under Inactive VDDM
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor devices with level shifter circuits face issues with inconsistent output signals and flow-through leak currents due to indeterminate voltage states, particularly when the voltage VDDM is inactive or indeterminate, leading to reliability concerns.
Innovation Solution
The semiconductor device incorporates an enabler circuit that generates a signal ENH_N based on the voltage VDDM, allowing the level shifter circuit to maintain a consistent output and suppress flow-through leak currents by outputting an 'H'-level signal when VDDM is inactive, and includes a NAND circuit to control power-saving operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the voltage VDDM is left inactive or indeterminate to save power, then power consumption is reduced, but the output signal becomes inconsistent and unreliable
Solution Approach 1:
The enabler circuit generates the control signal ENH_N in advance based on the state of voltage VDDM, ensuring that the level shifter circuit receives proper control signals before the voltage becomes indeterminate. This preliminary action prevents output inconsistency while allowing VDDM to be inactive for power saving.
Solution Approach 2:
The enabler circuit acts as an intermediary between the voltage VDDM and the level shifter circuit. It translates the indeterminate voltage state into a definite control signal ENH_N that properly controls the level shifter, thereby mediating between power saving and output reliability.
2Adaptability or versatility
If the level shifter circuit operates with indeterminate voltage VDDM, then circuit functionality is maintained, but flow-through leak currents increase
Solution Approach 1:
The enabler circuit monitors the state of voltage VDDM and provides feedback control through signal ENH_N to the level shifter circuit. This feedback mechanism ensures that the level shifter properly responds to the voltage state, preventing inappropriate current flow while maintaining circuit functionality.
Solution Approach 2:
The enabler circuit serves as an intermediary that controls the level shifter circuit's operation based on the voltage VDDM state. It prevents direct harmful interaction between the indeterminate voltage and the level shifter, thereby reducing leak currents while preserving functionality.
Data Source
AI summary
A semiconductor device includes an I/O circuit configured to be supplied with a first voltage, a second voltage higher than the first voltage, and a third voltage higher than the second voltage, and to receive an input signal based on the first voltage. The I/O circuit includes an enabler circuit configured to be supplied with the second voltage, and to generate a first signal based on the second voltage, and a first level shifter circuit coupled to the enabler circuit, and configured to, based on the first signal, level-shift a signal based on the second voltage to a signal based on the third voltage.