Buffer Dummy-Current Control for Stable Data Transmission Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Data transmission devices experience variations in power supply voltage due to switching operations, leading to reduced followability of power supply voltage and increased deviations in duty ratios and skew between clock signals and data, which affect data transmission reliability.
Innovation Solution
Incorporating a current circuit that generates a dummy current to compensate for buffer current variations, controlled by a control circuit that adjusts the dummy current based on the voltage level and transmission timing of data signals, thereby maintaining a constant current flow through the power supply line and reducing voltage variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a driver performs switching operation to set transmission data level, then data transmission function is achieved, but power supply voltage varies
Solution Approach 1:
The current circuit generates a dummy current in advance to counteract the current variation caused by buffer switching. When the buffer switches between high and low levels, the dummy current is adjusted to compensate for the current change, thereby preemptively preventing power supply voltage variation before it affects data transmission reliability.
Solution Approach 2:
The control circuit monitors the switching state of the buffer and dynamically adjusts the dummy current accordingly. This feedback mechanism ensures that the dummy current always opposes the buffer current variation, maintaining stable power supply voltage despite continuous switching operations during data transmission.
2Ease of operation
If buffer switching operation is performed, then data signal level is controlled, but followability of power supply voltage deteriorates
Solution Approach 1:
The system preemptively generates a dummy current that opposes the buffer switching current. By calculating the expected current variation from buffer switching and generating an equal and opposite dummy current, the power supply voltage maintains its ability to follow the required voltage levels without degradation from switching operations.
3Stability of the object's composition
If dummy current is generated to compensate buffer current variation, then power supply voltage stability is improved, but device complexity increases
Solution Approach 1:
A current circuit is introduced as an intermediary component between the power supply and the buffer. This mediator generates the dummy current that compensates for buffer switching variations, isolating the buffer from direct power supply fluctuations and simplifying the overall control logic while maintaining voltage stability.
Solution Approach 2:
The control circuit performs multiple functions: it monitors the buffer switching state, calculates the required dummy current magnitude and direction, and controls the current circuit accordingly. This multi-functionality reduces the need for separate dedicated circuits for each function, thereby limiting the increase in device complexity.
Data Source
AI summary
According to one embodiment, a data transmission device includes a buffer circuit configured to set a voltage level of a data signal to high or low, a power supply line for supplying a power supply voltage to the buffer circuit, a buffer control circuit configured to control a switching operation of the buffer circuit, a current circuit configured to make a dummy current flow to the power supply line, and a current control circuit configured to control the dummy current based on one of the set voltage level and a transmission timing of the data signal.