SIB2316 Sensor Interface Board SensL SPMArray2
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Vertilon Corporation, 66 Tadmuck Road, Westford, MA 01886
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Tel: (978) 692-7070
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Fax: (978) 692-7010
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www.vertilon.com
SPMArray2 Cathode Connections
Connection to the SPMArray2 device A and device B can be made using top-side FPC connectors J1 and J2
respectively. These connectors allow the SPMArray2s to face downward when connected to the SIB2316. Alternatively, if
the optical setup requires that the SPMArray2s face upward, then the bottom-side FPC connectors J9 and J10 can be
used. Regardless of the connectors used, the 16 cathode signals (IN01 – IN16) from each SPMArray2 are routed on the
SIB2316 to SIB connector J3 as shown in Figure 4. The cathode signals from device A are AC coupled and map to inputs
P1 through P16 on the connector, and likewise cathode signals from device B are AC coupled and map to inputs P17
through P32. The SIB connector mates to a proprietary low-noise, high density SIB cable assembly that carries the
detector signals on coaxial connections to a Vertilon PhotoniQ 32 channel data acquisition system. Depending on the
required speed and dynamic range, either a PhotoniQ IQSP480 high dynamic range system or an IQSP580 high speed
system can be used as the main data acquisition unit. The charge sensitive preamplifiers on the PhotoniQ integrate the
current signals from the detectors while maintaining a bias (Vb) near ground on the individual AC coupling capacitors.
Because the SPMArray2 devices are of the common anode type, the current polarity to the PhotoniQ preamplifiers is
out of the inputs. For this reason, the Input Polarity under the Data Configuration menu in the PhotoniQ GUI should be set
to the default value of positive. See the PhotoniQ user’s manual for more details.
Pulse Preamplifiers
There are many applications including PET and SPECT that require precise event timing pickoff from the SiPM detector
device. Specifically, acquisition of the event data needs to be accurately timed and synchronized with the detection of
particles on one or more of the elements in the SPMArray2. In fact, PET applications impose an additional condition on
event acquisition known as coincidence detection whereby triggering should only occur when near-simultaneous events
from each array are detected within a predefined time period. The SIB2316 contains dual event timing chains (one for
each SPMArray2) that are used for charge signal measurement, pulse discrimination, coincidence detection, and event
acquisition triggering.
Event timing begins with the pulse preamplifiers. The input signals to the preamplifiers are the current sense outputs from
the detector common anode bias generators. The current sense is a measure of the total current to all 16 detectors in an
SPMArray2 and is therefore a practical and precise means for detecting charge generated from particles that hit the SiPM
device. The SIB2316 pulse preamplifiers are variable gain transimpedance devices designed to accurately produce a
positive-going voltage output in response to a high speed input charge pulse. Their gain as well as all other SIB2316
parameters is adjusted using the dialog box shown on the next page available through the PhotoniQ GUI. Precision low
skew timing is achieved by using matched high bandwidth, low noise amplifiers. For diagnostic and monitoring purposes,
the outputs from the A and B preamps are available on SMB jacks J7 and J8, respectively. These outputs can also be
used as inputs to other external equipment such as time-of-flight measurement systems.
Summary of Contents for SIB2316
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