Agilent Technologies E1401-90493

Chapter 2 379

Performance Verification Tests

50. Gate Delay Accuracy and Gate Length Accuracy: Agilent E4401B, E4402B, E4404B,

E4405B, and E4407B (Option 1D6)

50. Gate Delay Accuracy and Gate Length

The method used for measuring the gate length times is determined by

the length of the gate. Shorter gate-length times are measured with an

oscilloscope, and longer gate-length times are measured with a counter.

For shorter gate-length times, the output signal of a pulse generator is

used to trigger the gate circuitry. To measure the gate delay, ∆t markers

are used. The oscilloscope pulse width measurement feature is used to

measure the short gate-length.

For longer gate-length times, a universal counter is used to measure the

time period from the rising edge of the gate output to its falling edge.

Because the gate-length time is equivalent to the clock accuracy of the

analyzer, the gate-length time is compared to the specification for clock

accuracy.

There are no related adjustment procedures for this performance test.

Equipment Required

Universal counter

Function generator

Oscilloscope (This procedure is written for the Agilent 54820A.)

Cable, BNC, 120 cm (48 in) (four required)

Adapter, BNC tee (m) (f) (f) (two required)

Procedure

1. Connect the equipment as shown in Figure 2-70. Connect the GATE

OUT to Channel 2.

2. Press Preset on the analyzer. Press the Factory Preset softkey, if it is

displayed. Set the analyzer by pressing the following keys:

SPAN, Zero Span

Sweep, Sweep Time, 100 s

Sweep, Gate (On)

Gate Setup, Edge Setup (or Edge Gate)

Gate Delay, 1 µs

Gate Length, 1 µs

NOTE The oscilloscope measurement is much more stable using slow sweep

times on the analyzer. The response on the analyzer display will not be

valid, but the Gate Delay and Gate Length accuracy are being

measured externally with the universal counter and oscilloscope.