SIS3820 multi purpose scaler


Multiscaler (MCS)

Latching Scaler

Preset Scaler

Histogramming Scaler

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The SIS3820 is the next step in Struck Innovatives continueing effort to develop state of the art scaler/counter boards and associated firmware for a variety of applications. It combines the functionality of standard counters and multiscalers without compromising performance. The use of standard commodity market memory solutions in combination with recent FPGA technology results in unprecedented functionality.

The SIS3820 scaler is a single width 6U VME card, no non standard voltages are required. The unit comes with a 20 pin header connector for the control section and two 34 pin headers for the counters (ECL and flat cable TTL version) or via 8 LEMO connectors for the control section and 32 LEMOs for the counter section (NIM and LEMO TTL version). RS422/RS485 is available as input option. The front panel design is compatible with the SIS380x. 32 additional inputs can be fed to the scaler via VME64x transition cards. The SIS3820 accepts inputs with a frequency of up to 250 MHz (50 MHz on the P2 fed inputs).

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Photograph of LEMO control, flat cable input module

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  • Single width 6U VME card
  • A16/A24/A32 D16/D32/BLT32/MBLT64/2eVME/CBLT
  • VME interrupt capabilities
  • Broadcast features
  • 32 channels (+32 channel option via P2
  • 4 control inputs and 4 control outputs
  • 64 MByte default (512 MByte optional) memory size
  • FIFO memory emulation mode
  • 24/32-bit channel depth
  • 250 MHz (ECL inputs)/50 MHz on rear inputs
  • ECL/TTL/LVDS or NIM inputs
  • Flat cable/LEMO mixed input configurations
  • External/VME time slice advance
  • Minimum dwell time 220ns (for 8 channels)
  • Synchronous clock shadow register
  • Read on the fly accuracy to lowest bit
  • 2 front panel user bits (in 24-bit mode)
  • copy in progress output
  • 2 x preset for arbitrary channel of 16ch group
  • Field upgradeable firmware
  • VME64x connectors, can be used in standard crates
  • VME64x side shielding
  • VME access/user LED
  • Single +5 V supply
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    Block Diagram

    SIS3820 block diagram vertical bar

    VME readout speed:

    Following block transfer speeds were measured with a SIS1100/3100 on a standard (i.e. non VME64x) VME backplane from the SIS3820s SDRAM.

    Transfer type Speed
    BLT32 25 MBytes/s
    MBLT64 50 MBytes/s
    2e VME 88 MBytes/s