Shared I/O Circuit for Differential and Single-Ended Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing input/output circuits require multiple signal lines for differential and single-ended signal transmission, leading to increased size and cost due to separate transmitter and receiver circuits for each signal type.
Innovation Solution
A single input/output circuit utilizing MOS transistors and constant-current sources that can operate in both differential and single-ended modes by switching between modes based on a differential enable signal, allowing shared signal lines and reduced circuit size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If differential signal transmission is used, then signal transmission speed is improved, but the number of signal lines increases
Solution Approach 1:
The receiver circuit is designed to universally handle both differential and single-ended signals through a single interface. The circuit includes a first receiver for differential signals and a second receiver for single-ended signals, both coupled to the same signal line, allowing the system to adapt to different signal types without requiring separate dedicated circuits for each mode.
Solution Approach 2:
The patent combines the differential receiver and single-ended receiver into a single integrated receiver circuit that shares common components including the first and second loads, first and second MOS transistors, and constant current sources. This merging allows both signal types to be processed through a unified structure, reducing the overall number of signal lines required.
2Reliability
If separate transmitter and receiver circuits are used for differential and single-ended signals, then signal transmission reliability is improved, but circuit size increases
Solution Approach 1:
The receiver circuit is designed to universally handle both differential and single-ended signals through a single interface. The circuit includes a first receiver for differential signals and a second receiver for single-ended signals, both coupled to the same signal line, allowing the system to adapt to different signal types without requiring separate dedicated circuits for each mode.
Solution Approach 2:
The patent combines the differential receiver and single-ended receiver into a single integrated receiver circuit that shares common components including the first and second loads, first and second MOS transistors, and constant current sources. This merging allows both signal types to be processed through a unified structure, reducing the overall circuit area while maintaining reliability.
3Reliability
If dedicated transmitter and receiver circuits are used for each signal type, then signal transmission quality is improved, but device complexity increases
Solution Approach 1:
The receiver circuit is designed to universally handle both differential and single-ended signals through a single interface. The circuit includes a first receiver for differential signals and a second receiver for single-ended signals, both coupled to the same signal line, allowing the system to adapt to different signal types without requiring separate dedicated circuits for each mode.
Solution Approach 2:
The patent combines the differential receiver and single-ended receiver into a single integrated receiver circuit that shares common components including the first and second loads, first and second MOS transistors, and constant current sources. This merging allows both signal types to be processed through a unified structure, reducing device complexity while maintaining signal transmission quality.
Data Source
AI summary
An input/output circuit has a first load having one end coupled to a first standard voltage line, a first MOS transistor having a drain electrode coupled to another end of the first load, a second load having one end coupled to the first standard voltage line, a second MOS transistor having a drain electrode coupled to another end of the second load, a third MOS transistor having a source electrode each of which is coupled to source electrodes of the first and second MOS transistors, a first constant-current source coupled between the source electrode of the first MOS transistor and a second standard voltage line, and a second constant-current source coupled between the source electrode of the second MOS transistor and the second standard voltage line. The circuit size is reduced by transmitting a differential signal or a single-ended signal using a single input/output circuit.