Clock Distribution for IceCube June 8, 2004 Lawerence Berkeley National Laboratory Gerald Przybylski...
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Transcript of Clock Distribution for IceCube June 8, 2004 Lawerence Berkeley National Laboratory Gerald Przybylski...
Clock Distributionfor IceCube
June 8, 2004
Lawerence Berkeley National Laboratory
Gerald Przybylski
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
2
Big Picture
ExacTime ET6000GPS Clock(s)
ExacTime ET6000GPS Clock(s)
DOM HubDOM HubDOM Hub
FanOut
1pps
10 MHz
Equal Length Twisted Pairs;10 Mhz, 1pps, RS-232;Cat5E with RJ-45s
SlavedRubidiumOscillatorInside, < 1x10-11
Allan Var.
US Naval Observatory(~1E-15 Allan Var. ) UTC
BalancedDrivers
Master Clock Unit
GTPrzybylski LBNL 6/8/2004
Serial
DOM HubDOM Hub~90 DOM Hubs
(With Oven Crystal option)
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
3
Rubidium Oscillator Allan Variance
Figure from http://www.srsys.com/products/PRS10.htm
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
4
Rubidium Clock Phase Noise
Figure from http://www.srsys.com/products/PRS10.htm
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
5
Accuracy and Precision
The US Naval Observatory20 Atomic Clock array keeps time to < 2x10-15.
GPS SatellitesSynchronized to USNO clock.
DOMs more stable than XL GPS clocks40ns RMS; 150ns Peak Error; 3E-10 10 sec Allan variance Radio Propagation Path variationsGPS Receiver Local Oscillator jitter.
In House Cable Delays; Fixed Phase ShiftsGPS Clock -to- Master Clock UnitMaster Clock -to- DOM Hub Fan-OutFan-out -to- DOR FPGA FPGA -to- Wire
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
6
Inside the DOM Hub
DO
R c
ard
DO
R c
ard
DO
R c
ard
DO
R c
ard
DO
R c
ard
DO
R c
ard
DO
R c
ard
DO
R c
ard
Clk
Fan
-Out
CP
U
Cable FromMaster ClockUnit 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 SuppliesFans
Monitors(PossiblyDiskless)
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
7
DSB:1-to-8SlaveClockFan-out(PCI
Card)
20 MHz Aux. Osc.
AlteraPLD
EPM7064
The DOR Card
Data Buffer
SRAM2 x 256Kx16
Cable Interface #0
Cable Interface #1
Cable Interface #2
Cable Interface #3
PCI-Core
FLASH1M x 8
Config JTAG
Altera FPGA
EP20K200E
JTAG
PCIBus
DOM 1..4
JTAG
96 V
DOM 5..8
10 MHz
1 pulse/second
(Serial) Time StringMasterClock
KHS 10-2003
GTPrzybylski LBNL 10/13/2003
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
8
Communications
ControllerAltera EP1C20F400C8
DOR_Rev1, Block Diagram
Data Buffer
SRAM2 x
256Kx16
Cable Interface #0
FLASH2M x 8
Config. PLDAltera
EPM7128BFC100-10
Config JTAG
JTAG
PCIBus
DOM 1..4
JTAG
Clock
+/-48 V
DOM 5..8
PCI Bus-Ctrl Altera
EP1K50FC256-1JTAG ConfigMemory Bus
Local Bus
PLLQS5LV9
19
local
Osc.
Power-sw. #1..4wired
OR Power-filter #1..4
nPON_1..4 nPON_1..4
Clock_sel
PCICore
DSB:1-to-8SlaveClockFan-out(PCI
Card)
20 MHz Aux. Osc.
MasterClock
1PPSSerial
Cable Interface #1
Cable Interface #2
Cable Interface #3
K-H Sulanke 6/8/.04
June 8, 2004 IceCube 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, 2004 IceCube DOMHub Hardware Review and Workshop
10
Master Clock to DSB
Like 802.3
RS-485
GTPrzybylski LBNL 6/8/04
June 8, 2004 IceCube DOMHub Hardware Review and Workshop
11
DSB to DOR
LVDS
GTPrzybylski LBNL 6/8/04
June 8, 2004 IceCube 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, 2004 IceCube 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, 2004 IceCube 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, 2004 IceCube 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