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User Guide
QuickSyn Lite Frequency Synthesizer
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Set Trigger
The radio buttons in the Sweep Settings (Common)
area of the Sweep Mode panel allow the user to set parameters that
are common to frequency sweeps.
• When No Trigger is selected, sweeps begin immediately after
selecting the Start Sweep button.
• When Enable List Trigger is selected and the Start Sweep button
is pressed, a full sweep of all list points begins when a hardware
trigger is detected.
• When Enable List Point Trigger is selected and the Start Sweep but-
ton is pressed, one sweep point is output for each hardware trigger
received.
Dwell Time (usec)
The Dwell Time entry box is used to enter the
dwell time, which is the time each point in the sweep will remain
static before moving to the next point. The dwell time is not used
when Enable List Point Trigger is selected. To enter a dwell time,
highlight the entry box and enter a value. Use the up/down arrow
on the left side to raise or lower the value.
Sweep Direction
The buttons under Sweep Direction allow the
user to set sweep direction.
• When Up is selected, sweeps occur from start frequency to stop
frequency.
• When Down is selected, sweeps occur from stop frequencey to
start frequency.
• When Up and Down is selected, the synthesizer sweeps in both
ascending and descending order.
Number of Sweeps
This entry box is used to define the number
of times a sweep is executed. To enter a number of sweeps,
highlight the entry box and enter the desired value. The up/down
arrow on the left side of the entry box can be used to increase or
decrease the value.
NOTE
A hardware trigger is a 0/3.3 V pulse signal applied to pin 14 (trigger) of the SPI
interface connector. A trigger is initiated on a low-to-high transition.
NOTE
Switching speed (from one frequency point to another) in Normal Mode is 200 μs.
Sweeps can be as fast as 100 μs per point in Fast Mode. However, the number of
points allowed is limited to 32,000. Therefore, use Normal Mode for sweeps that
require a number of points over 32,000.
