Memory Cell Programming Circuit with Precharge Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for programming non-volatile memory cells face inefficiencies in controlling current, leading to excessive programming time and power consumption, especially in multi-level data storage where precise current control is crucial.
Innovation Solution
The implementation of improved circuitry and methods that isolate memory cells during a precharge phase and apply a controlled program current, allowing for a higher precharge current without damaging the cells, ensuring precise programming.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a long programming pulse is applied to guarantee every memory cell is programmed, then programming reliability is improved, but programming time and power consumption increase excessively
Solution Approach 1:
The patent implements a detection circuit that monitors the programming state of memory cells in real-time and provides feedback to the control circuit. When the detection circuit determines a memory cell has reached the programmed state, it signals the control circuit to terminate programming for that cell, enabling early termination and reducing average programming time while maintaining reliability
Solution Approach 2:
The patent dynamically adjusts the programming pulse duration based on individual cell programming status rather than using a fixed long pulse for all cells. The control circuit modulates the programming operation based on real-time detection feedback, allowing shorter pulses for cells that program quickly while ensuring worst-case cells still receive sufficient programming time
2Manufacturing precision
If a series of short high-voltage programming pulses is applied with reading pulses in between, then programming control is improved, but time and power overhead from switching between program and read voltages increases
Solution Approach 1:
The patent extracts the voltage switching operation from the programming sequence by maintaining the programming voltage throughout the entire programming operation. The detection circuit operates at the same voltage level as programming, eliminating the need to switch between program and read voltages and removing the associated time and power overhead
Solution Approach 2:
The detection circuit is designed to function at the programming voltage level, making it universal for operation during the programming phase. This multi-functional approach allows the detection circuit to monitor cell state without requiring separate read voltage operations, integrating detection and programming into a single voltage domain
3Manufacturing precision
If short programming pulses are used instead of long continuous pulses, then programming control is improved, but energy efficiency deteriorates
Solution Approach 1:
The detection circuit provides real-time feedback on programming completion status, allowing the control circuit to terminate programming as soon as a cell reaches the programmed state. This prevents unnecessary continuation of pulses after programming is complete, reducing energy consumption while maintaining precise control through the feedback mechanism
Solution Approach 2:
The patent applies programming pulses selectively based on individual cell needs rather than uniformly to all cells. Cells that program quickly receive shorter effective programming duration, while cells requiring more time receive extended pulses, optimizing energy efficiency by avoiding excessive action on cells that are already programmed
4Speed
If higher precharge current is applied to speed up precharging, then precharge speed is improved, but risk of damaging memory cells during precharge increases
Solution Approach 1:
The patent segments the precharge operation from the programming operation by using separate current paths. A precharge current path delivers high current to bitlines for rapid precharging, while a separate programming current path controls the current through memory cells during programming, preventing damage by isolating the high-current precharge effect from the cell programming process
Solution Approach 2:
The patent introduces a precharge switch as an intermediary component between the precharge current source and the memory cell programming path. This switch allows the precharge current to be applied to bitlines without directly flowing through memory cells, mediating the high-current precharge operation to protect cells while enabling fast precharging
5Quantity of substance
If multi-level data storage is implemented requiring more than two distinct current levels, then data storage capacity is improved, but accuracy control over program current becomes more important and more difficult
Solution Approach 1:
The patent implements dynamic current control where the programming current is modulated in real-time based on detection feedback. For multi-level storage, the control circuit adjusts current magnitude and duration dynamically to achieve precise current integration levels, enabling accurate differentiation between multiple storage states through controlled current profiles rather than fixed current levels
Data Source
AI summary
Improved circuitry and methods for programming memory cells of a memory device are disclosed. The improved circuitry and methods operate to isolate the memory cells from potentially damaging electrical energy that can be imposed during a precharge phase that precedes programming of the memory cells. Additionally, the improved circuitry and methods can operate to ensure that programming of the memory cells is performed in a controlled manner using only a program current. The improved circuitry and methods are particularly useful for programming non-volatile memory cells. In one embodiment, the memory device pertains to a semiconductor memory product, such as a semiconductor memory chip or a portable memory card.