Transcript Straw electronics status

Straw electronics status
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Signal generation and formation in straw
Webs
Cover
Backend
TTC
Services
Signal creation and formation
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Still not understood
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CARIOCA measured on test bench
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CARIOCA connected to straw DOES NOT conform
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Analog signal much wider
Less multiple pulses then predicted
Time resolution worse
Tonino analysis
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Noise and gain comparable with other measurements and articles
Our home-made CARIOCA model yields similar results
Bad straw resolution at the test beam can be attributed to high noise
As the high noise is NOT observed otherwise, Signal-to-Noise ratio must
be responsible, hence signal is smaller than expected
If signal is smaller, detector calibration (threshold) is wrong
Why the signal is smaller?
Signal creation and formation
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Still not understood
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Few theories to test
Electric field in straw is changing and thus the signal
Part of signal is radiated out as EM wave
Crosstalk to other objects takes away the high speed
component
Straw as a transmission line does not behave as we expect
External and parasitic components play more important role
then expected
Signal creation and formation
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Signal from the straw –
reversed engineering
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Try to get the signal shape
from known CARIOCA
response and measured
Fe55 signal shape (ideal
single cluster response
due to point-like
ionization)
Red measured Fe55
response
top black is the straw
current creating bottom
black response
Signal is ‘stretched’ by 1015ns
Signal creation and formation
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Study of the straw signal
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Simulation
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Assumes that the signal created is the standard 1/(t+t0)
Try to account for all the parasitic components and straw transmission
properties
Few pF on termination and active web is dramatically changing reflections
and charge transfer
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Ideal termination is impossible
Measurements of parasitics
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New passive web without resistor: 2.6pF
Old passive web without resistor: 2.7pF
New active web alone: 4.3pF
New active web with cover : 20.6pF
old active web alone: 7.4pF
old active web with cover : 24pF
Signal creation and formation
Simulation with AMS (CADENCE version of SPICE)
Signal creation and formation
CARIOCA input current as a function of termination and distance (0.2m -> 2m)
Ideal source
1/(t+5ns)
‘ideal’ 360 Ohm
termination
Open (but with
web parasitics)
100 Ohm
termination
Signal creation and formation
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Ongoing studies
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On a single straw test bench study the straw transmission
properties
Straws on detector prototypes gradually equipped with webs
Study signal from straw with high-speed current preamp with
Fe55/cosmics
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Design finished, PCB ordered
Due to moving of production facilities delayed for 27.7.2011
Web production and assembly
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Webs
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Left and right intermediate
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2 pieces of each
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Assembled and ready for test with old covers
Left and Right active
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35 pieces of each (33 not assembled)
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Problem HV, trace too close to HV via
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Number of tests done up to 3kV, problem not observed, long-term reliability?
Left and right passive (termination)
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6 pieces of each (29 PCB not finished)
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Possible problem with HV but less serious then active
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Number of tests done up to 2.5kV (no current observed, limit by HV supply)
New production due to possible problem with HV
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Ordered 8 pieces of left and right active
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Delayed to before 27.7.2011
Components
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Connectors received
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Capacitors delayed
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500 each type
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12 000 ordered
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Shipped from USA week ago
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Need to order more for passive web (need total 16000)
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Resistors for active web
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Resistors for passive web
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12000 at home
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Value not fixed
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220 Ohms for tests
Covers production and assembly
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New covers with
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3 pieces of CELL4 produced and ready for assembly
3 pieces of CELL3 in PCB production
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New connector
On-board TDC
Connection via ethernet cable
Delayed last week of July?
All components ready for 6 pieces
Backend
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SRB prototype
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Designed to be able to readout
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4 old covers
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4 new covers
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Power supply part not finished
Ready for PCB design this week
TDC in FPGA
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Ethernet connectors
High speed links
Buffer for ~100,000 events
TTC interface with TTCRx and clock cleaning by QPLL
Number of extra NIM and LVDS input/outputs for synchronization and other (unforeseen) functions
Design almost finished
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VHDCI connector
TDC on SRB
Patch panel not needed as all services come from SRB
Finally understand the behavior
Usable with 0.78 ns bin
More Andrea
TEL62
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Need 2 or 4 pieces
It should be placed close to the detector
Share special TEL62 crate and TTC distribution with other detector?
TTC
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2 sets of LTU+TTCex ordered
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The distribution scheme re-discussed
Each of 4 chambers has got a TTC link with 1:16 splitter
for 12 SRBs and possibly 1 TEL62
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1 set used in experiment
1 set in lab and spare
TEL62 to be discussed with other detectors
TTCex equipped with 4 lasers
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Either each laser drives directly chamber link
Or we use optical 1:4 splitter and keep 3 lasers as spare
(failure rate of lasers not known)
Questionnaire for Service Inventory
Services
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Racks
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Each chamber has
got 1 rack
Should be less then
5 meters from the
chamber due to
cables
1 VME 9U crate for
SRBs
2 MPOD crates
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1 needed at the
moment
Spare place for 1
more depending on
frontend
electronics
Sub-Detector or System:
Straw tracker
Form filled by:
Peter Lichard, CERN
Date:
17.5.2011
Straw detector needs at the moment 1 rack per chamber. There are 4 chambers, 2 before and 2
after magnet. Ideally, racks for 2 chambers should be placed together at the equal distance from
both chambers. All 4 racks are identical, description is below.
There is also a possible need for 1 or more racks for housing 9U and 6U VME crates for TEL62 and
TTC system. These could be eventually shared with other subdetectors.
The needs of DCS system are not yet known. It is possible that to each rack we would need to add an
industrial (rack mountable) PC and monitor.
Type of Crate
How many Unit
Power in 220V (VA)
Power in 380V (VA)
Other Power?
Normal Network
Diesel Network
UPS Network
Comments
Power needed (KW)
Type of cooling
Other Cooling?
Comments
Nb of HV cable
Ø for 1 HV cable
Nb of LV cable
Ø for 1 LV cable
Nb of fibre
Ø for 1 fibre
Nb of signal cable
Wiener VME
9U
3000
NO
NO
YES
NO
NO
Electrical Requirements
Wiener
Wiener
MPOD
MPOD
9U
9U
3600
3600
NO
NO
NO
NO
YES
YES
NO
NO
NO
NO
Cooling and Ventilation Requirements
3
3.6
3.6
AIR
AIR
AIR
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Water?
Water?
Water?
Cable and Fibres between Detector and Rack
NO
8
NO
NO
5mm
NO
no
16
16
10mm
10mm
NO
NO
NO
NO
NO
NO
120
NO
NO
Power supply
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Proposal to use MPOD system from Wiener
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Modular system with
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1 chamber needs at the moment 1 MPOD crate with
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~70 kEuro
Checking the possibility to receive an evaluation system
ESE-BE (POOL) group also interested
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OPC ethernet server for DCS
No local control/display
8 pcs MPV2008, LV-voltage module for MPOD system, 2 DC channels, floating, programmable 0...8V/40A (max 250W each)
1 pc EHS 8220x_405 F, 8-channel HIGH PRECISION HV-module for MPOD-System, 2000V/ 4mA , SHV, Polarity (x=p/n)
Offers received for 4 crates (full detector without spares)
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8U crate with bottom and top cooling air inlets
Possibility to house both HV and LV modules
Up to 3kW/crate
Possibility to introduce the system to CERN on more general basis
Help with testing and evaluation
Need HV patch panel with HV relays to be able to switch-off cells with a problem
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Relay indentified (~17 Euros)
Controlled by ELMB (need more ELMBs)
Needed for final detector