Agilent Technologies 16760A manual 257

Chapter 6: Concepts

Understanding State Mode Sampling Positions

Sample Position Adjustments on Individual Channels

To position the setup/hold window (sampling position) within the data valid window, a logic analyzer has an adjustable delay on each sampling clock input (to position the setup/hold window for all the channels in a pod).

Some logic analyzers let you adjust the position of the setup/hold window (sampling position) on each channel. When you can make sampling position adjustments on individual channels, you can make the logic analyzer's setup/hold window smaller because you can correct for the delay effects caused by the probe cables and the logic analyzer's internal circuit board traces, and you are left with the setup/hold requirements of the logic analyzer's internal sampling circuitry.

However, the process of manually positioning the setup/hold window for each channel is time consuming. For each signal in the device under test and each logic analyzer channel, you must measure the data valid window in relation to the bus clock (with an oscilloscope), repeatedly position the setup/hold window and run measurements to see if the logic analyzer captures data correctly, and finally position the setup/ hold window in between the positions where data was captured incorrectly.

In Agilent Technologies logic analyzers which have the eye finder feature, you can automatically position the setup/hold window on each

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