Change-over circuit from CMOS to MCML

Abstract

The invention provides a CMOS-MCML conversion circuit, which is used for the conversion between a single-end output CMOS circuit and a double-end input MCML circuit. The conversion circuit is composed of a differential circuit which comprises a pair of differential tubes, a pair of loads and an offset tube; the input end of a differential tube of the pair of differential tubes is connected with the output end of the CMOS, and the output end of the differential tube is connected with the input end of the other differential tube; the output ends of the pair of differential tubes are used as two input ends of the MCML circuit. As the output end of a differential tube is used as the input end of the other differential tube, an extra signal generating circuit is effectively saved; the problems of power supply noise, output jitter and high conversion noise found in traditional differential circuit are effectively reduced; the problem that when the input end of a differential tube introduces external reference voltage, the output voltage has small swing, affects the work performance of subsequent MCML circuit and reduces the circuit speed is solved.

Description

technical field [0001] The invention relates to the design field of conversion circuits between different types of circuits, in particular to a conversion circuit from CMOS to MCML. Background technique [0002] At present, CMOS (Complimentary MOS) is a very common type of logic circuit used in digital logic circuits. Since CMOS circuits have negligible quiescent current, this makes them dominant in digital integrated circuits. In digital logic circuits, MOS current mode logic circuits (MOS Current Mode Logical) have faster speed, lower power consumption and stronger immunity to power supply noise than CMOS circuits in the application of high-speed circuit systems. These advantages make MCML circuits have a dominant position in the design of high-speed and high-performance integrated circuits. However, in the system on a chip (SOC) design, in order to obtain a high-performance SOC at a lower cost, both CMOS circuits and MCML circuits are applied. [0003] In this way, it ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a conversion circuit from CMOS to MCML to solve the problem of needing an additional input signal generation circuit or reference voltage circuit, as well as the problem of large power supply noise and output jitter in traditional conversion circuits and a conversion circuit with a reference voltage circuit The output voltage swing is small and the problem that affects the performance and speed of the subsequent MCML circuit

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