Download Annexure – 1 to the Tender Enquiry No.DPS/AMPU/MIC/1704

Annexure – 1 to the Tender Enquiry No.DPS/AMPU/MIC/1704
Technical Specification of Electronics for scintillation detector
assembly- Model: SDA- 01
CPU/Controller
: 16 bit PIC Controller @ 20MHZ
Count capacity
: 9999999999(10 digits)
Acquisition time
: programmable in seconds
Built-in Memory
: EEROM 256Kbytes
DATA communication
: RS485 port two numbers
Pulse Amplifier
:
Low noise high input impedance input stage to receive negative pulse from
photomultiplier anode section of scintillation detector and polarity conversion,
Gaussian shaping amplifier with pole-zero cancellation, Software tunable gain
amplifier for gamma energy calibration, Buffer stage before window analyzer,
Window analyzer with tunable reference, Software tunable Noise reference 0-3V,
High voltage
:
Low power, very low ripple DC-DC converter to generate 300V to 1300V high
voltage software tunable, bias for photomultiplier load of 5M, Necessary shielding to
eliminate noise interference caused by switching and magnetic circuits of DC-DC
converter.
Power Requirement
: 12V DC @ 50mA or less in full load
Operational/Features
:
remember last set/used operational parameters and work on those parameters till
new parameters entered, Acquired data with date and time stamp, stored data
erased on demand only, provision to load default settings
PMT base resistor chain : Circular PCB with 5.1M/440K resistor chain between
dynodes with proper filter capacitor and providing pulse point and HV bias point.
Console
:
All above hardware assembled in moisture proof aluminium /metal unit with two 5pin
connectors to connect with Host System/ PC. Enclosure should have provision to
accommodate one 2” x 2” NaI(Tl) crystal & Photomultiplier tube integral assembly,
above HV and pulse processing circuit, PMT base resistor chain PCB with moisture
proof enclosure.
Software
:
Software to provides acquisition of data from detectors and transmit counts/data to
the host (BUOA) system / PC, probe software accept the operational commands
through RS485 protocol from host system (RTOS)/ PC and execute the routines to
acquire data or set the HV bias to photomultiplier tube, change the acquisition time,
Auto calibration procedure with a mono energy gamma source etc. Software to be
provided with multiple debug messages to check probe error, HV error, Count zero
error etc. Necessary mathematical computations need to be included in the software
to calculate the sample grade. Software for generation/controlling of the High
voltage, counting of digital logical pulses, shaping and processing of detected bipolar
spiked signal from scintillation detector into Gaussian pulse with auto gain
adjustment with a known gamma source, RS485 interface and power supply
circuitries.