User manual

5-22 Return to Section Topics 3390-900-01 Rev. C / January 2009
Section 5: Waveform Output Operations Model 3390 Arbitrary Waveform Generator User’s Manual
If the burst period is set too short, the instrument automatically adjusts it to the shortest
value (up to its maximum) that can accommodate the specified burst count and waveform
frequency:
Burst period > (Burst Count ÷ Waveform Frequency) + 200 ns
•External trigger source: External trigger source delivers a burst each time a TTL pulse
with specified polarity is received at the Trig In/Out connector on the rear panel. The
instrument ignores any trigger signals received during the output of a burst. Burst period is
not applicable.
•Manual trigger source: Manual trigger source delivers a burst with each press of the
Trigger key. Burst period is not applicable.
Trigger out signal
The instrument can be set to deliver a trigger out signal at the Trig In/Out connector on the rear
panel. This signal can be enabled when the instrument is set for internal or manual triggered burst
mode, and it is synchronized with the burst output.
Trigger out signals perform as follows:
•Internal trigger source: A square waveform with 50% duty cycle is delivered at the Trig
Out connector at the beginning of the burst.
•Manual trigger source: A pulse is delivered (with pulse width > 1 µs) at the Trig Out
connector at the beginning of each sweep.
To set up burst output:
1. Select the carrier waveform (Sine, Square, Ramp, or Arb. Noise is permitted in gated burst
mode only). Follow the instructions for setting up that specific waveform as given in this
publication. Refer to Section 4, Setup Basics for assistance.
2. Press the Burst key to access the burst menu.
3. Press the soft key under N Cyc / Gated to choose between the triggered and external gated
modes (Figure 5-18). Ensure your selection is highlighted.
Figure 5-18:
Press the soft keys corresponding with trigger selection (internal triggering shown)
• Triggered burst mode:
a) Press the soft key under #Cyc / Inf to choose between finite and infinite burst
count:
• Finite burst count: Ensure that #Cyc is highlighted. Use the navigation wheel with
the cursor keys to change the value, and then press another soft key to finish the
entry and exit. Or use the numeric keypad to enter a desired value and then press
the soft key under Cyc to finish the entry, or the soft key under Cancel to cancel
the changes.
• Infinite burst count: Ensure that Inf is highlighted. The display will automatically
highlight the Start / Phase selection. Use the navigation wheel with the cursor
keys to change the value, and then press another soft key to finish the entry
and exit. Or use the numeric keypad to enter a desired value and then press the
soft key under Deg to finish the entry, or the soft key under Cancel to cancel
the changes.