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SiPM digital control board supporting components (view source)
Revision as of 15:16, 5 November 2009
, 15:16, 5 November 2009→LED-less RJ-45 Jack
The Xilinx XCF01S EEPROM is responsible for configuring the FPGA when the system is turned on or reset. We selected the XCF01S because it is recommended by Xilinx as the best solution for programming the Spartan-3A FPGA used on the control board. The XCF01S is ideal because it has sufficient memory to hold the entire FPGA program, and also minimizes the number of FPGA-to-EEPROM leads necessary for programming the FPGA. For more information on the mode of programming the FPGA, see [[FPGA programming modes]].
The Xilinx XCF01S EEPROM is responsible for configuring the FPGA when the system is turned on or reset. We selected the XCF01S because it is recommended by Xilinx as the best solution for programming the Spartan-3A FPGA used on the control board. The XCF01S is ideal because it has sufficient memory to hold the entire FPGA program, and also minimizes the number of FPGA-to-EEPROM leads necessary for programming the FPGA. For more information on the mode of programming the FPGA, see [[FPGA programming modes]].
Both the EEPROM and the FPGA are designed to tolerate +3.3V CMOS logic levels, keeping the configuration logic at the same voltages as the other logic on the board.
=== Post-Configuration EEPROM Isolating Logic ===
=== Post-Configuration EEPROM Isolating Logic ===
=== LED-less RJ-45 Jack ===
=== LED-less RJ-45 Jack ===
Since we want to keep the enclosure as dark as possible, we must use an Ethernet jack with no built-in activity/link LED. There are many suitable jacks available. Most likely, we will want a shielded jack such as the Stewart Connector Systems SS-6488S-A-NF ([http://search.digikey.com/scripts/DkSearch/dksus.dll?pname?site=us;lang=en;name=380-1024-ND Digi-Key Part #380-1024-ND]). However, there are many other LED-less jacks available that may also be suitable. For a listing of other LED-less jacks, look at the [http://digi-key.dirxion.com/Main.asp?from=emailafriend&pagenav=&bookid=2&pageindex=306 Digi-Key Interactive Catalog].
Since we want to keep the enclosure as dark as possible, we must use an Ethernet jack with no built-in activity/link LED. There are many suitable jacks available. The jack we have selected to use on the board is the Pulse Engineering J0012D21.