SIB164B PMT Sensor Interface Board for Hamamatsu H7546B / H12428 Series
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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
Photomultiplier Tube Anode Circuits
The 64 anode signals (P1 – P64) from the PMT are routed directly on the SIB164B to two specialized connectors referred
to as sensor interface board (SIB) connectors. Anodes P1 to P32 route to SIB connector J1 and anodes P33 to P64 route
to SIB connector J2. Each SIB connector mates to a proprietary low-noise, high density SIB cable assembly that carries
the 32 anode signals on coaxial connections to a Vertilon PhotoniQ 64 channel PMT data acquisition system. Depending
on the required speed and dynamic range, either a PhotoniQ IQSP482 high dynamic range system or an IQSP582 high
speed system can be used as the main data acquisition unit. To minimize the possibility of damage due to ESD, the
PMT’s anodes each have a 2.2 Mohm shunt resistor to a common low impedance point. This point is biased at a voltage
equal to the bias voltage (VB) of the charge integrating transimpedance amplifiers on the PhotoniQ so that the PMT
anodes can be DC coupled to them. Figure 4 below illustrates the equivalent circuit as seen by each PMT anode.
Figure 4: Anode Circuit
Last Dynode Preamplifier
This last dynode preamplifier is an inverting, AC-coupled, two-stage configuration whose input is designed for small
positive voltage pulses from the last dynode (DY12) of the H7546B / H12428. The gain of the preamplifier is set by the
user through the PhotoniQ GUI dialog box shown on the next page. For specialized applications requiring external
discrimination or coincidence logic of the last dynode signal, the preamplifier output is available on SMB connector, J6.
Alternatively, the preamplifier output can be further processed by one of the two different discriminators on the SIB164B
to generate trigger signals in sync with the pulse on the last dynode.
