Interfacing NI PXI-655x Digital Waveform Generator/Analyzers to ECL Logic Families

Download it now!

Login first to download.

First used in the mid-1960s, emitter-coupled logic (ECL) is an important logic family predominantly because of its ability to operate at very high speeds. Additionally, because ECL is a differential standard, it offers better noise immunity than single-ended standards such as TTL. This application note will discuss three methods for interfacing single-ended NI PXI-655x digital waveform generator/analyzers to ECL logic:

Single-ended ECL
Differential ECL
Using an off-board TTL-ECL translator

Interfacing to PECL (positive emitter-coupled logic) can be done using these same methods; however, you must
change the acquisition and generation voltage levels of the PXI-655x. In fact, some ECL buffer chips can change
between the two logic families by simply changing the polarity of their power supply.