Center-Swing CML-to-CMOS Conversion for Full-Rail Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current integrated circuits face challenges in converting low-swing Current Mode Logic (CML) differential signals to full rail single-ended signals efficiently, which limits power consumption reduction and noise rejection across high-speed applications.
Innovation Solution
The system employs a center-swing signal generator, push-pull center-swing driver, common-mode pre-emphasis module, and full-swing cross-coupled inverter gain stage to convert low-swing CML signals into full rail single-ended signals, utilizing transistors and current mirrors to manage voltage swings and reject common-mode noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If low-swing CML differential signaling is used for high-speed data transfer, then power consumption is reduced and supply voltage is lowered, but conversion to full rail single-ended signal is required which increases complexity
Solution Approach 1:
The patent introduces a center-swing signal generator as an intermediary component that converts low-swing CML differential signals to center-swing signals, which are then converted to full-rail single-ended signals. This two-stage conversion process using an intermediate representation resolves the direct conversion complexity while maintaining power efficiency benefits
2Adaptability or versatility
If CML and CMOS circuitry are combined in a single integrated circuit, then circuit functionality is enhanced, but signal conversion between differential and single-ended formats increases device complexity
Solution Approach 1:
The center-swing signal generator is designed to handle multiple signal types and conversion modes, serving as a universal interface between CML differential signaling and CMOS single-ended signaling. This multi-functional component reduces overall system complexity by consolidating conversion functionality
3Object-affected harmful factors
If full rail single-ended signal conversion is implemented, then noise rejection is improved, but power consumption increases
Solution Approach 1:
The conversion circuitry uses periodic switching actions in the push-pull driver stage to achieve full-rail voltage swings only when needed for noise rejection, rather than continuously operating at full power. This periodic operation maintains noise immunity while reducing average power consumption
Data Source
AI summary
Apparatus, systems, and methods are disclosed, such as those that comprise a center-swing signal generator that includes a push-pull center-swing driver coupled to a common-mode pre-emphasis module, the center-swing signal generator to receive a low swing current mode logic (CML) signal and output a center-swing signal, and a full-swing cross-coupled inverter coupled to the center-swing signal generator, the full-swing cross-coupled inverter to receive the center-swing signal and output a full-rail single-ended swing signal. Additional apparatus, systems, and methods are disclosed.