Racal Instruments 3152A, Руководство пользователя

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3152A User Manual
Racal Instruments
©
2001 Getting Started 1-9
The trigger signal, whether it comes from the front panel or from
the VXIbus, has to pass through circuitry. These circuits cause a
small delay known as system delay. System delay cannot be
eliminated completely. It is, however, minimized in the Model
3152A to approximately 200ns maximum. System delay is a
factor that must be considered when applying a trigger signal. It
defines how long it will take from a valid trigger edge to the
moment that the output reacts.
While system delay cannot be controlled, the Model 3152A
offers a controllable trigger delay parameter. When utilized,
delay from a trigger signal to output waveform may be
programmed from 0 clocks to one million clocks. This delay is
additional to the system delay.
Burst Mode
The burst mode is an extension of the triggered mode where the
Model 3152A can be armed to output a counted number of
waveforms following a triggered signal. Like trigger mode, burst
can be triggered from a front panel BNC connector, a VXIbus
backplane TTLTRG<n> or from an internal, programmable
trigger generator.
Gated Mode
In gated mode, the Model 3152A circuits are armed to generate
output waveforms as long as a gating signal is true. Unlike the
triggered mode, the gated mode is level sensitive. When the
gating signal goes false, the waveform at the output connector is
first completed and the output goes to an idle state. The stop
amplitude level, after a gating signal, is the last point on the
waveform.
Output Type
The Model 3152A can output three types of waveforms: standard
waveforms, arbitrary waveforms and sequenced waveforms.
The three types of waveforms are described in the following.