BNC 745 - Manual (Page 15)

Model 745 Digital Delay Generator. November 2013
Timing principle using external trigger
When the device is in a rest state (no current output signals), a rising edge on a trigger starts a delay
sequence. The trigger comes from TRIG IN, or from a software command trigger (depending on the
selected channel source).
The sequence includes two external trigger phases:
• After an insertion delay (<60ns), a pulse appears on each channel after a specified delay
• At the end of sequence, after the last delayed pulse, the delay generator is ready for
repetitive trigger mode.
When a sequence is in progress, the instrument does not respond to a trigger event.
The MOD745 must be configured (trigger, delay, etc.) before starting any sequences.
Figure - 6. External Trigger Timing
In response to an input pulse the board can generate a single delayed output (single shot) or
repetitive delayed output (repetitive mode with a Trig In prescaler value = 1). As explain before, the
single shot pulse is conditioned by the soft trigger command.
The use of the Prescaler value is depicted on Figure - 7. T1 Channel trigger source is set to external
trigger.
© Berkeley Nucleonics Corp. 14 Model 745 User Manual