DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw1 DES Collaboration Meeting Front End Electronics Status T. Shaw, D. Huffman, M. Kozlovsky, J. Olsen, W. Stuermer (FNAL) T. Moore, V. Simaitis (UIUC) M. Barceló, L. Cardiel (IFAE) J. Castilla, J. DeVicente, G. Martinez (CIEMAT) P. Moore, R. Schmidt (NOAO)

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw2 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 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

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw3 Monsoon Readout System is the chosen platform for test and production electronics 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

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw4 Monsoon Crate MCBCBB8-Ch CCD Acq.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw5 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 <10e - noise at ~12us/pixel.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw6 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 located outside of dewar wall, we are able to achieve ~6.5e - noise at ~6us/pixel with a long cable July 2006 Delivery of fourth Monsoon system for FNAL August 2006 FNAL Director’s review recommends use of JFET source follower close to CCD video output October 2006 Begin instrumenting the Multi-CCD test Dewar (MCD) December 2006 Simultaneous readout of two CCDs in MCD.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw7 Proposed Changes to Monsoon To use the Monsoon System for Production DES Electronics, 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. –Build a customized Clock Board to better address our clocking needs; greater fanout ability to drive more clocks. –Slight modification to the Master Control Board to allow for switch to S-Link as the fiber optic link; also, look into multi-crate synchronization

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw8 12-Channel Board Why do we need to change the Monsoon Acquisition Board? System density –Limited space in proximity to the telescope. Increasing the Video Channel count to 12 to better match the system. Improved Control of CCD Biasing. –Better trimming of HV Biases –Control of Substrate voltage rise/fall time (Ramp). Adding Temperature read back for RTD sensors.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw9 CCD Acquisition Card Description 12 Video Signal Channels AC Coupled 18-bit ADC (same as Monsoon!) –Dynamic range and Sensitivity 4V pk/pk 15.6uV/ADC –Dual Slope Correlated Double Sampling (CDS) with DC Restoration –Offset controlled to maximize dynamic range –Maximum 250 kpixel/sec –Noise <3 ADU rms 48 High Voltage Biasing Signals (Telemetry) –12 bit DAC adjustable between fixed range. –12 bit ADC read back on each Bias channel –Outputs can be Enabled/Disabled via software control Micro-Sequencer Pattern Memory –Drives the Analog Front End circuits when triggered across the Back Plane. On-Board Temperature Sensor (10 bits) 6 Channels for RTD temperature sensors on CCD –12 bit ADC with Sensor Current Source Single FPGA for control: JTAG programmable Board Identification –Unique Digital Serial Number –Firmware Version –Board Type

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw10 CCD 12 Channel Acq. Board Temp. Sensor Digital Serial Number Reset Interface 6 Chan RTD 12 bit ADC Telemetry Interface X48 12 bit DAC Interface X48 18 bit ADC Interface X12 CDS Interface X12 Back Plane RAM Memory  -Sequencer FPGA 900 pin BGA JTAG Prog. Transition Card (12 Video Channel Inputs)

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw11 Top View

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw12 Bottom View

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw13 12-Channel Transition Module

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw14 DES New Clock Board New Clock Board is being designed by engineers at CIEMAT (Madrid) which will drive many more clock lines. The current NOAO board provides 32 clocks, the new board will provide 135, or enough for 9 CCDs.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw15 9 CCDs CB-36 clk Backplane MAIN board Transition CRATE 135 clk VIDEO Board DES Clock Board Concept CCD 3 X 15 CLK CCD 3 X 15 CLK 9 CCDs CCD 3 X 15 CLK CCD 3 X 15 CLK CB-36 clk Transition 135 clk

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw16 FPGA 36 CLK Voltage swing generation 135 Cable Drivers Hardware redesign MONSOON CBB DES CB supply Telemetry 32 CLK BIAS CPLD FPGA BIAS section removed 4 clock generation channels added 135 cable drivers included on board 2 CPLD removed supply Telemetry

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw17 Firmware redesign BIAS control removed Code integration: from 2 CPLD+FPGA to 1 FPGA New microsequencer development microsequencer SEQ BUS (write) TELEMETRY MUX FRONT PANEL DAC/ADC CONFIG ADCs DACs FRONT PANEL 36 Clocks BackPlane Interface PATTERN MEMORY (DUAL PORT) PROGRAM COUNTER GENERATION CLOCK TRIGGER REGISTER PIXDATA BUS (read) FPGA

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw18 Status: –Schematics and layout ready –Firmware ready for testing –Prototype is under production Future work: –CB testbench installation in Madrid (Monsoon based) –Prototype validation and characterization Clock board status

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw19 Barcelona work/Master Control Board Waiting for Laia’s slides… should cover s-link, multi-crate synchronization, transition cards

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw20 PF Packaging 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.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw21 Vacuum Interface Board(VIB) 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.

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw22 Vacuum Interface Board Kapton Cable AlN Board Camera Vessel Instrumentation

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw23 Power Supply Studies Ongoing work by engineers at the University of Illinois on testing power supply performance. Goal is to prove viability of switching power supplies. Tests were run with Linear supplies and Vicor supplies attached to original Monsoon 6-slot DHE. Remote sensing was removed & local sensing added. Noise measurements are taken with video inputs connected to ccd emulator

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw24 UofI Monsoon Test Stand Wiring Scheme

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw25 Linear Supply Plot Results

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw26 Vicor Supply Plot Results

DES Collaboration Meeting, Chicago, December 11-13, 2006 T. Shaw27 Conclusions