Logic analyzer
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Image:1615a logic analyzer.jpg
A logic analyzer displays signals in a digital circuit that are too fast to be observed by a human being. A logic analyzer captures digital data from a digital system that has too many channels to be examined with an oscilloscope and presents it to a user so that the user can more easily check correct operation of the digital system.
Operation
A logic analyzer would trigger on a complicated sequence of digital events, and then copy a large amount of digital data from the system under test. The best logic analyzers behaved like software debuggers (showing the flow of the computer program), or oscilloscopes.
When logic analyzers first came into use, it was common to attach several hundred "clips" to a digital system. Later, specialized connectors came into use. In modern computer systems various other tools have made logic analyzers obsolete for many uses. For example, many microprocessors have hardware support for software debuggers. Many digital designs, including those of ICs, are simulated to detect defects before the unit is constructed. The simulation usually provides logic analysis displays. Often, complex discrete logic is verified by simulating inputs and testing outputs using boundary scan. None of these exactly reproduce the high-speed data capture function of a logic analyzer, but they cover many real needs for debugging digital circuits.