Electronic eye timer generator#

In the real world, even a reasonably good and quite acceptable digital signal will exhibit some amount of amplitude and timing variation, which will show up as discrete lines that are not exactly where they belong but will nonetheless suffice. Ideally, the eye diagram for digital signals would consist of two parallel lines with an instantaneous rise and fall times virtually invisible. For example, if a run of cable were to have a fault caused by pinch or kink, eye diagrams observed at both ends would differ, and the cable could be repaired or more likely the entire run could be replaced. It is a simple matter to probe different locations in a circuit, looking at the eye diagram, to localize any problems. We see displayed a succession of waveforms one upon another. On the right, we use Multipurpose Knob a to set the oscilloscope for infinite persistence. From the menu across the bottom, we press the soft key that corresponds to Waveform Display. To demonstrate using a Tektronix MDO3104 oscilloscope, we connect the AFG output on the back panel to an analog input channel on the front panel and press AFG so a sine wave displays.

The eye diagram is used primarily to look at digital signals for the purpose of recognizing the effects of distortion and finding its source. It is created simply by superimposing successive waveforms to form a composite image. The eye diagram takes its name from the fact that it has the appearance of a human eye. Here, the bit sequences 011, 001, 100, and 110 are superimposed over one another to obtain the example eye diagram.

Electronic eye timer generator#

To generate a waveform analogous to an eye diagram, we can apply infinite persistence to various analog signals a well as to quasi-digital signals such as square wave and pulse as synthesized by an arbitrary frequency generator (AFG).

An eye diagram is used in electrical engineering to get a good idea of signal quality in the digital domain.