SIB916 Sensor Interface Board for Broadcom AFBR-S4N44P163
- 16 -
Vertilon Corporation, 66 Tadmuck Road, Westford, MA 01886
/
Tel: (978) 692-7070
/
Fax: (978) 692-7010
/
www.vertilon.com
Trigger Output
The trigger output produces a
well-behaved
logic signal from either the discriminator or the coincidence detector. When
the discriminator is enabled and the coincidence detector is off, the discriminator is internally connected to the trigger
output. In this mode, the trigger output becomes active when the discriminator goes high and remains active until the
discriminator goes low. However, for very short duration discriminator pulses, the trigger output will remain active for a
minimum period of time (t
pw,min
). This is shown in the figure below. If the discriminator is enabled and the coincidence
detector is on, the trigger output is directly connected to the coincidence detector output with no further signal processing.
The trigger output polarity for the active state can be set to either
positive
or
negative
logic for either operating mode.
Figure 10: Minimum Pulse Width Condition
LED Indicator
The multi-color LED indicates the triggering status of the SIB916. When the coincidence detector is not used, the LED
blinks green when an event is detected and is off when no event is detected. The LED blinks red if the user sets the
discriminator threshold to a value near the discriminator baseline level creating an error condition. This is most likely near
the point where the minimum trigger output condition occurs. The LED has slightly different behavior when the
coincidence detector is used. Here the LED blinks green when a coincidence event is detected, yellow when there is an
event on either input but no coincidence, and off when there is no event. The LED can be selectively enabled and
disabled in the SIB916 GUI dialog box.
Temperature Sensor
An on-board temperature sensor is located on the bottom side of the SIB916 near the SiPM array. The sensor reports the
temperature of the circuit board in degrees Celsius to the PhotoniQ graphical user interface. This information is useful for
determining the proper bias to the SiPM array. Temperature data is not logged to a file by the PhotoniQ data acquisition
system.
V
th
t
d
TRIGGER
OUTPUT
INPUT
CURRENT
PREAMP
OUTPUT
t
pw, min
Summary of Contents for AFBR-S4N44P163
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