Clock Distribution for IceCube June 8, 2004 Lawerence Berkeley National Laboratory Gerald Przybylski GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 2 Big Picture ExacTime ET6000 GPS Clock(s) ExacTime ET6000 GPS Clock(s) DOM Hub Fan Out 1pps 10 MHz Equal Length Twisted Pairs; 10 Mhz, 1pps, RS-232; Cat5E with RJ-45s Slaved Rubidium Oscillator Inside, < 1x Allan Var. US Naval Observatory (~1E-15 Allan Var. ) UTC Balanced Drivers Master Clock Unit GTPrzybylski LBNL 6/8/2004 Serial DOM Hub ~90 DOM Hubs (With Oven Crystal option)

June 8, 2004IceCube DOMHub Hardware Review and Workshop 3 Rubidium Oscillator Allan Variance Figure from GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 4 Rubidium Clock Phase Noise Figure from GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 5 Accuracy and Precision The US Naval Observatory 20 Atomic Clock array keeps time to < 2x GPS Satellites Synchronized to USNO clock. DOMs more stable than XL GPS clocks 40ns RMS; 150ns Peak Error; 3E sec Allan variance Radio Propagation Path variations GPS Receiver Local Oscillator jitter. In House Cable Delays; Fixed Phase Shifts GPS Clock -to- Master Clock Unit Master Clock -to- DOM Hub Fan-Out Fan-out -to- DOR FPGA FPGA -to- Wire GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 6 Inside the DOM Hub DOR card Clk Fan-OutCPU Cable From Master Clock Unit 20 MHz (Orange Twisted Pair) 1 Pulse per Second (Green Twisted Pair) RS-232 Time String (Brown Twisted Pair) Internal, equal length fanout cables Power Supplies Fans Monitors (Possibly Diskless) GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 7 DSB: 1-to-8 Slave Clock Fan-out (PCI Card) 20 MHz Aux. Osc. Altera PLD EPM7064 The DOR Card Data Buffer SRAM 2 x 256Kx16 Cable Interface #0 Cable Interface #1 Cable Interface #2 Cable Interface #3 PCI-CorePCI-Core FLASH 1M x 8 ConfigJTAG Altera FPGA EP20K200E JTAG PCI Bus DOM 1..4 JTAG 96 V DOM MHz 1 pulse/second (Serial) Time String Master Clock KHS GTPrzybylski LBNL 10/13/2003

June 8, 2004IceCube DOMHub Hardware Review and Workshop 8 Communications Controller Altera EP1C20F400C8 DOR_Rev1, Block Diagram Data Buffer SRAM 2 x 256Kx16 Cable Interface #0 FLASH 2M x 8 Config. PLD Altera EPM7128BFC ConfigJTAG PCI Bus DOM 1..4 JTAG Clock +/-48 V DOM 5..8 PCI Bus-Ctrl Altera EP1K50FC256-1 JTAG Config Memory Bus Local Bus PLL QS5LV919 local Osc. Power-sw. #1..4 wired OR Power-filter #1..4 nPON_1..4 Clock_sel PCI Core DSB: 1-to-8 Slave Clock Fan-out (PCI Card) 20 MHz Aux. Osc. Master Clock 1PPS Serial Cable Interface #1 Cable Interface #2 Cable Interface #3 K-H Sulanke 6/8/.04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 9 Signaling Issues: Maximize Noise Immunity in Counting House - Avoid Winter Noise Storms - Avoid Motor Noise, Welder Noise, etc… Minimize EMI and RFI - Computers and Instruments Proven Technology - Price - Component Availability - Track Record GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 10 Master Clock to DSB Like RS-485 GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 11 DSB to DOR LVDS GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 12 Master Clock Features [PY03, this year] Single ET6000 (Xtal, or Rubidium?) - OCXO: 10 Sec Allan Variance 2E-11, -120 dBc/Hz Phase Noise - Rubidium: 10 Sec Allan Variance 1E-11, -91 dBc/Hz Phase Noise 10 MHz from Half the Optional Outputs - Drive LEMO Inputs through coax 1 Hz from Half the Optional Outputs - Drive LEMO Inputs through coax RS-232 from (DTR) DB-9 - Daisy-Chain cable Cold Spare in Rack Heated “Radome” on TCH Roof (>-40°C) GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 13 PY03 Deployment GPS Clock (Hot) DOM Hub, String 0 DOM Hub, String 1 DOM Hub, String 2 DOM Hub, String 3 Temporary Counting House BOM: GPS Clock 4 identical BNC to LEMO cables (10 MHz) 4 identical BNC to LEMO cables (1 PPS) 1 Serial daisy-chain cable (Time String) Antenna Heater 10 MHz 1 PPS Serial Port cable GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 14 Master Clock Features [Post PY03] Multiple GPS clock inputs (?) - Fail-over (?); Voting (?) Status display (?) - Local Time display - Fault indicator - Fault Reporting - Selected Clock Clock Relay Port feeding back to MAPO (?) - Supply AMANDA with the IceCube Ref Clock CPU Monitoring Functions via POE, or CAN (?) - Voltages, Temperatures, Fans - CPU Reset; Power on/off GTPrzybylski LBNL 6/8/04

June 8, 2004IceCube DOMHub Hardware Review and Workshop 15 Summary DSB to DOR card Functionality Demonstrated GPS clock Drive to DSB demonstrated Firmware under development (Sulanke) possible involvement by LBNL too… DSB usable, as is, at the Pole for first deployment Oven Crystal GPS Clock in hand (ExacTime ET6000) Simplified Deployment Plan Exists for this year. GTPrzybylski LBNL 6/8/04