cmos ecl converter with high speed and low phase shift

摘要

A logic level converter for translating CMOS logic signals to into differential logic signal pairs such as those associated with ECL levels. The converter includes a first converter branch (20) coupled to the switchable CMOS level input and it provides a first switchable translated output (A). A second converter branch (30) is not coupled to the input nor is it coupled to the first converter branch. The second converter branch provides a fixed reference signal output (B) around which the output (A) of the first converter branch (20) switches. Changes in the input signal to the first converter branch cause its output potential to be more than or less than the potential of the fixed reference signal (B) supplied by the second converter branch (30). The components of the respective branches may be tailored to position the fixed signal at a selectable level and to define the differential between the two output signals. The current associated with the converter is mirrored through both branches to minimize the effects of fabrication, temperature, and/or power supply vagaries. IMAGE