Output Buffer Initialization Circuit for Multi-Chip Package Data Integrity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-chip packages, the power-up or power-down of one memory device can affect the data output of another memory device due to impedance changes in the output buffer, leading to potential data loss or errors.
Innovation Solution
An output buffer initialization circuit that activates an output buffer reset signal during power-up or power-down and deactivates it based on a command signal from the controller, maintaining the output port in a high impedance state to prevent interference with data output from other memory devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the output buffer is enabled during power-up or power-down of one memory device, then the output buffer can output data, but the data output from other memory devices is affected due to impedance changes
Solution Approach 1:
The output buffer initialization circuit activates the output buffer reset signal before normal operation begins, during the power-up or power-down phase. This preliminary action ensures the output buffer is in a known high-impedance state before data output operations start, preventing data corruption from other memory devices
Solution Approach 2:
The output buffer reset signal acts as an intermediary control signal between the power management system and the output buffer. It mediates the transition of the output buffer between high-impedance and normal operating states, ensuring proper timing and preventing data conflicts in multi-chip packages
2Reliability
If the output buffer reset signal is activated during power-up or power-down, then data output from other memory devices is protected, but the output buffer cannot output data simultaneously
Solution Approach 1:
The output buffer reset signal is activated periodically during specific phases (power-up or power-down) rather than continuously. This periodic activation maintains data integrity when needed while allowing normal data output operations to proceed during active phases, resolving the contradiction between protection and productivity
3Productivity
If the output port maintains low impedance state, then data can be output efficiently, but data from other memory chips is affected due to interference
Solution Approach 1:
The output buffer dynamically changes its impedance state based on operational requirements. During power-up or power-down phases, it maintains high-impedance state to prevent interference. During normal operation, it switches to low-impedance state for efficient data output. This dynamic adaptation resolves the contradiction between efficiency and interference prevention
Data Source
AI summary
A semiconductor device has at least two semiconductor memory devices, each of which includes a memory cell array arranged in a matrix of rows and columns, a peripheral circuit writing data to a cell of the memory cell array and reading out and amplifying the written data, and an output buffer outputting cell data amplified by the peripheral circuit. The output buffer includes an output buffer initialization circuit activating an output buffer reset signal in response to the power up or power down of the semiconductor memory device and deactivating the output buffer reset signal in response to a first command signal output from a controller of the semiconductor memory device, and an output driver generating output data based on a data signal in response to a clock signal, a data enable signal, and the output buffer reset signal.