Readout Electronics: SIDECAR ASIC

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• Readout Electronics SIDECAR ASIC
• Hardware

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SIDECAR ASIC

• Two sets of Control Electronics used ARC and
  SIDECAR ASIC
• SIDECAR has great functionality very powerful
  chip
• Challenge is to write assembly code to achieve
  functionality

SIDECAR FEATURES 36 Analog Inputs 20 Digital I/O
Clocks 20 Output Biases 36 16 bit ADCs 36 12 bit
ADCs
Taken from Loose et al. SPIE 2002
Taken from Loose et al. SPIE 2007
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SIDECAR ASIC and H4RG

• SIDECAR ASIC set up at Rochester Imaging Detector
  Laboratory
• All Clocks and Biases probed during power-up and
  regular operation
• No Voltages above 3.3 V
• going to detector
• SIMPLE INTERFACE

HXRG
Hirose Connector
ASIC
JADE
SIDECAR ASIC attached to an H4RG and connected to
DELL Laptop with a USB cable Have tested ASIC
over 125 foot fiber/USB cable
Computer
USB Cable
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External Electronics Data from ASIC
CONFIG AND SCIENCE DATA TO/FROM SIDECAR

Spartan 3- FPGA Xilinx Firmware written by
Teledyne
JADE CARD
No Unix libraries or source code available for
USB microcontroller! Only precompiled .dll files
containing classes.
EZ-USB FX2LP(TM) USB Microcontroller Quick USB
DLL written by Bitwise

MICROSOFT COM FUNCTIONS HalWrapper.dll written in
C and .NET
COMPUTER
IDL Code or Other interface
IDE Written by Teledyne
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Setup used at ESO
Figure taken from Dorn et al. Evaluation of the
Teledyne SIDECAR ASIC, SPIE 2006

• - Cryogenic ASIC sits inside dewar
• Standard LGA socket packaging provided by
  Teledyne

JADE Card sits outside of dewar JADE not used by
SNAP team
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• Readout Electronics SIDECAR ASIC
• Firmware
• Note Fine details, likely not necessary for
  Corner Raft Meeting

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SIDECAR Video Inputs

• SIDECAR ASIC has capacitively coupled inputs
• Capacitive feedback used for gain
• Leakage currents cause voltage at node to rise
• Very noticeable at room temperature
• Must reset capacitors periodically to prevent
  large rise
• Problem kTC noise

Amplification S3 and S6 are open
Special sample and hold circuitry able to sample
voltage on Cfb as reference
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kTC Noise Removal

• Reset PreAmps once per frame
• Drift of voltage is apparent over the frame
• Reset PreAmps once per row
• Different voltage due to kTC noise appearing on
  caps is visible from row to row
• Reset PreAmps once per row with kTC removal
• Row to row noise is eliminated

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SIDECAR ADC Averaging

• Noise of ADCs is 2 ADU
• To beat it down, average input on multiple ADCs
• Input Routing Mux allows you to sample one input
  on 1-8 channels

Simplified Portion of Routing Mux
Detector Video Output
Channel 7
Channel 6
Channel 5
Channel 4
Channel 3
Channel 2
Channel 1
Channel 0
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ADC Averaging Results

• Noise goes down as 1/ as expected
• Only works if 4 or less outputs of HxRGs are used
• Second generation of SIDECAR ASIC expected to
  have lower noise