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Figure 2.16 shows the functionality of the gate timing and delay unit. Active gate time is

marked in green.

Trigger

Gate

Gate Start

Gate Stop

Figure 2.16: Gate and delay functionality: When a trigger occurs, the gate opens after a set

period of time (“gate start”) and closes when it reaches “gate stop”.

Gating Example 1: Suppression of Noise After Starting an Acquisition

In mass spectrometer and other experiments, noise while starting data acquisition can result

in undesired trigger events for that time period. To prevent noise in the output data, a gating

block could be used to suppress all triggers during start-up.

The following example illustrates the use of a gating block to prevent noise: The GATE input

transmits a pulse on each acquisition start. The trigger structure of the GATE input is used to

select pulse polarity. Then, the GATE trigger is selected as gating block input and the gating

block’s start parameter is set to 0. The stop parameter is set to the desired length measured in

3.2ns clock cycle and negate is set to true. The gating block will now output a low pulse of the

desired length whenever there is a pulse on the GATE input.

Enabling this gating block as an AND input to the trigger block, for which noise shall be

suppressed.

Gating Example 2: Delayed Trigger

To sample a short window at a speciﬁed time after a trigger event on a channel, the gating

block can be used to create a delayed trigger. To do this, one of the triggers of the channel of

interested is conﬁgured to the desired parameters by selecting the threshold, setting the edge

polarity and enabling edge triggering.

Instead of directly using this trigger as input to the trigger block’s input matrix, the trigger

is selected as an input to a gating block. The block is conﬁgured to start = delay and stop =

start + 1, negate = false. This causes the gating block to produce a one clock cycle pulse on

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