21
X-Cite® mini+ User Guide
035-00587R rev. 5
5.2
TTL
For high speed LED on/off control, TTL triggering can be used. The key thing to note about TTL control in
the X-Cite® mini+ is: TTL mode MUST be enabled for the system to respond to a TTL signal.
5.2.1
TTL Mode
TTL mode ensures that X-Cite® mini+’s cooling system and LED driver are active between
exposures, ensuring the fastest possible response to a TTL signal.
Enabling/disabling TTL mode can be accomplished manually via speedDIAL (refer to
section 4.3.4) or via computer commands (refer to SDK).
ON/OFF status of the system will be updated on speedDIAL when it is controlled via TTL.
5.2.2
TTL Mode Timeout
There is a potential disadvantage of TTL mode - in this “always active” state, the system
continues to consume energy and mechanical components accumulate wear. To help minimize
unnecessary consumption at the end of an imaging session (or if equipment is accidentally left
on), X-Cite® mini+ is equipped with a TTL timeout setting. The factory default for the TTL
timeout setting is “Never”, but defining a timeout is recommended for any imaging session that
will end without an operator present to shut down equipment (e.g. middle of the night).
Figure 9 Sequence of Events for TTL Mode Timeout (set to 4 hours)
5.2.3
TTL Timing Diagram
This plot shows typical TTL timing values. These values should be used as a guide only. Actual
values will be dependent on the specific configuration/control hardware being used.
LED off
Timeout clock resets,
begins countdown
(unit stays active)
TTL mode times out
(drivers/cooling turn off, TTL
mode remains enabled)
LED on
(response at maximum speed)
Time
elapses
LED on
(after drivers and cooling wake up)
time 4h,
TTL high
4h
TTL high
TTL low
TTL low
