DES Review

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DES Review

• DES Front End Electronics
• WBS 1.3
• T. Shaw

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DES FE Project Definition

• We must read out a large focal plane of CCDs
• 62 Science CCDs
• 8 Alignment CCDs
• 4 Guide CCDs
• The Science and Alignment CCDs are read out at
  the same rate with the same clocking patterns
• 250k-pixels/s _at_ 10e- rms noise
• The Guide CCDs will be readout at a faster rate
  will not interfere with required quiet time of
  Science and Alignment CCDs

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DES FE Electronics WBS structure
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LBL CCD
CCD Bond Pads
2048 x 4096 15 µm pixel CCD
Vertical clocking moves charge towards
serial register
Horizontal clocking moves charge along serial
output register to video output amplifiers
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Signal Count per CCD

• Each CCD will require control of the following
  signals
• Horizontal clocking
• H1_U, H1_L, H2_U, H2_L, H3_U, H3_L, SW, RG
• Vertical clocking
• V1, V2, V3, TG
• Erase control
• n guard
• Bias voltages
• Vr_U, Vr_L, Vdd, Vopg, Vsub
• Totals 13 clocks per CCD
• 5 bias levels per CCD
• Tuning of optimal CCD readout is accomplished
  by adjusting clock rail voltages and bias
  settings. We are assuming, relying on current
  test results, that production readout can group
  at least 3 CCDs together with like clock rail
  settings.

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CCD Packaging Picture FrameWBS 1.3.1
CCD is wire bonded to a polymide board
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CCD Packaging Pedestal PackageWBS 1.3.2
37-pin Nanonics Dualobe connector
CCD is wire bonded to an AlN board
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Monsoon Readout SystemWBS 1.3.6

• Monsoon
• Developed by NOAO
• Crate based system (Eurocard format)
• cPCI backplane used (no cPCI protocol)
• Open Design
• Schematics available
• Firmware available
• Layout files available
• Boards exist
• Master Control Board
• Clock and Bias Board
• 8 Channel Acquisition Board
• Large software framework exists
• http//www.noao.edu/ets/monsoon/

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Monsoon Block Diagram
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Monsoon Crate
MCB
CBB
8-Ch CCD Acq.
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History of Monsoon at FNAL

• Mid 2004
• DES group looks into the Leach and Monsoon
  Systems as possible readout solutions. Leach is
  an established proprietary readout system for
  CCDs. Monsoon offered some advantages higher
  density (8 channel card vs 2 channel card of
  Leach) telemetry readout (readback of clock rail
  voltages and bias voltages) designed for large
  mosaics open architecture easy to customize.
  (Lots of manpower already expended by NOAO on
  Monsoon 12 engineering years/5 programmer
  years/5 board layout years.)
• University of Illinois Urbana-Champaign began to
  purchase the initial Monsoon test stands.
• March 2005
• FE workshop at FNAL decision to continue to
  pursue Monsoon as readout platform.
• April 2005
• Receive MCB, CBB and a blank prototype 8 ch CCD
  Acq Board to be hand assembled.
• Never able to achieve low noise.
• Nov 2005
• Delivery of 2 complete Monsoon systems (MCB, CBB
  and production 8 ch CCD Acq Board).
• Fairly quickly began running with lt10e- noise at
  12us/pixel.
• Jan 2006
• FNAL takes delivery of Leach System. Leach
  performance quickly matches Monsoon performance.
• Feb 2006
• FEE Panel formed to examine choice of design
  platform. Specifically, to look at Leach and
  Monsoon.

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History of Monsoon at FNAL

• Feb 2006
• Delivery of two additional complete Monsoon
  Systems. One was shipped to Barcelona
• Mar 2006
• With short cable run, we are able to achieve
  6.5e- noise at 6us/pixel
• April 2006
• With a pre-amp (WBS 1.3.5) located outside of
  dewar wall, we are able to achieve 6.5e- noise
  at 6us/pixel with a long cable
• June 2006
• FEE Panel tasked with examining choice of Monsoon
  vs Leach comes back with its findings.
• In summary
• Monsoon work seems to be progressing
• Keep an eye on 12 Channel Board design fallback
  to use current 8 Channel Board
• Leach Controller remains a viable alternative in
  case of unforeseen problem with Monsoon.
• July 2006
• Delivery of fourth Monsoon system for FNAL

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Pre-amp Board (WBS 1.3.5) currently outside of
dewar
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Proposed Changes to Monsoon

• To use the Monsoon System for DES, we will
  customize the boards for our specific
  application
• Build a 12 channel CCD Acq Module which would
  provide customized bias voltages, RTD readout,
  and Vsubstrate ramp control. (WBS 1.3.8)
• Build a customized Clock Board to better address
  our clocking needs greater fanout ability to
  drive more clocks. (WBS 1.3.7)
• Slight modification to the Master Control Board
  to allow for switch to S-Link as the fiber optic
  link. (WBS 1.3.9)
• Breakout session will cover these new board
  designs in more detail.

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PF Packaging WBS 1.3.10

• UIUC has worked with FNAL mechanical engineers
  and proposes to instrument the telescope using
  three FE crates.
• These crates would each contain two backplanes
  one with 6 slots and one with 4 slots.
• A single 4-slot section would provide for readout
  of up to 9 guide CCDs
• The remaining backplane sections would provide
  readout of up to 72 science and alignment CCDs.
• UIUC is also providing engineering support for
  crate power supplies.

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Vacuum Interface Board(VIB) WBS 1.3.4
Vacuum Interface Board will provide the
connection between the Monsoon boards and the
CCDs on the focal plane. Monsoon cables will
plug into the VIB outside the vacuum. Kapton
cables will be used to connect between Vacuum
Interface Board and the CCDs inside the dewar.
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Camera Vessel Instrumentation
Kapton Cable WBS 1.3.3
Vacuum Interface Board WBS 1.3.4
AlN Board WBS 1.3.2
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DES FE Electronics L3 Milestones
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Monsoon Electronics Schedule Milestones
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DES Electronics Schedule Milestones
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Engineering Teams/Responsibilities

• FNAL
• (T. Shaw, D. Huffman, M. Kozlovsky, Jamieson
  Olsen, Walter Stuermer)
• Instrumentation of CCD testing stations
• 12 Channel CCD Acq Module Transition
• Vacuum Interface Board
• Cabling
• Pre-amps
• UIUC
• (T. Moore, V. Simaitis)
• Crate
• Power Supply
• Barcelona
• (Laia Cardiel, Miquel Barceló)
• Clock Bias Board Fanout Transition Module
• Clock Board Transition
• Master Control Board
• Madrid
• (Gustavo Martinez, Javier Castilla, Juan De
  Vicente)
• Clock Board

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FE Electronics Costs
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Conclusions

• FE Readout is based upon the Monsoon system. This
  is working for the readout of our small test
  dewars. New customized Monsoon modules are being
  designed to address specific DES requirements.
• Leach remains as a fallback to the Monsoon
  readout solution.
• Next plans
• Readout an array of CCDs in the large test dewar.
• Optimize cable design location of pre-amp.

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Backup slide
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Monsoon Quantity/Cost estimates