Current Sensing Amplifier Power Reduction via Op-Amp Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional current sensing amplifiers for non-volatile memory devices have high power consumption due to the need for a DC bias current in operational amplifiers, which affects their efficiency during read cycles.
Innovation Solution
A current sensing amplifier method that uses a reference unit and sensing units with constant voltage providing circuits and latching circuits, where the sensing node and reference node are pre-charged to a constant voltage, and the storing state is determined by comparing the sensing voltage with a preset voltage after connecting with a cell current and reference current, respectively, without the need for an operational amplifier.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an operational amplifier is used in the current sensing amplifier, then the sensing function can be implemented, but the power consumption increases due to DC bias current requirements
Solution Approach 1:
The patent extracts and removes the operational amplifier component from the current sensing amplifier circuit. By eliminating the op-amp, the design eliminates the need for DC bias current, thereby resolving the power consumption issue while maintaining the sensing function through alternative circuit topology using transistors M1-M3 and comparator CMP
Solution Approach 2:
The patent replaces the expensive and power-hungry operational amplifier with a simpler, lower-cost transistor-based clamp circuit and comparator architecture. This substitution uses basic transistors and a comparator that consume significantly less power while achieving the same sensing objective
2Reliability
If a conventional current sensing amplifier with operational amplifier is used, then the storing state can be determined, but the device complexity increases
Solution Approach 1:
The patent extracts the operational amplifier from the circuit and replaces it with a simpler transistor-based clamp circuit (M1, M2, M3) and comparator architecture. This reduction in component complexity maintains the storing state determination function while simplifying the overall device structure
Solution Approach 2:
The patent segments the sensing function into distinct modular components: a clamp circuit using transistors M1-M3 for current sensing, and a separate comparator CMP for voltage comparison and state determination. This segmentation creates a simpler, more manageable circuit architecture compared to a monolithic operational amplifier design
Data Source
AI summary
A sensing method of a current sensing amplifier is provided used for determining a storing state of a cell of a non-volatile memory device during a read cycle. After a sensing node and a reference node are adjusted to a constant voltage, the sensing node and the reference node are maintained in a floating state. Then, the sensing node is connected with a data line to receive a cell current from the cell, and the reference node is connected with a reference current source to receive a reference current from the reference current source. When a reference voltage of the reference node reaches a preset voltage, the storing state of the cell is determined according to a relationship between a sensing voltage of the sensing node and the preset voltage.