Proposed US Contribution to the Wide Field Imager

PSUMITJHU

History

• PSU, MIT, and SAO approached about four years ago to contribute to IXO WFI instrument.

• Proposed US contribution to IXO WFI was in the ICU hardware and software.– This provided a clean interface between US and European

hardware.– Drew upon decades of combined US experience with X-ray

imaging instruments• Murray/SAO-JHU: Einstein HRI, ROSAT HRI, Chandra HRC• Bautz/MIT: ASCA SIS, Chandra ACIS, Suzaku XIS, Astro-H SXI • Burrows/PSU: Chandra ACIS, Swift XRT

US Response to L2

• Paul Hertz (director of NASA’s Astrophysics Division) has expressed interest in contributing to an L2 mission at a level of up to $150M.

• The US X-Ray Science Interest Group (XRSIG) prepared a list of possible US contributions to ESA’s L2 mission for Paul’s consideration. This list included a US contribution to the ATHENA WFI instrument along the lines of the IXO contribution.

• ESA Call for L2 Mission Concept proposals clearly permits US contributions to Instrument Teams

• The current WFI architecture is similar to the IXO WFI architecture as of summer 2010

High speed fiber optic data link proposed

2048 x 2816 pixels total, read out every 2 μs (?) => 1 Gpix/s – 1.5 Gpix/s

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Proposed US contribution to WFI

US contribution

US contribution: ICU •Provides clean interface between US and European responsibilities•Capitalizes on initial development of high-speed event recognition•Propose fiber optic data transfer bus to WFI

Movable Instrument Platform

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Instrument Control Unit (ICU) Concept

Based on IXO WFI / June 2010

Fiber Optic interface• Assumed 8 optical fibers (for IXO/WFI)

– Mass < 500 g– Power < 3W– Cost ~ $70K – Double numbers for redundancy

• Requires use of Xilinx FPGAs to interface to optical fiber transceivers– Xilinx Virtex-5QV FPGAs are rad-hard, 1 Mrad dose– Virtex-5 are fast enough, >3 GHz multi-gigabit serial

IXO WFI Instrument Control Unit Block Diagram June 2010 D. Burrows

Spacecraft Com

GSE connection

Power

Science Data

Housekeeping Data

Slow Control Bus

Housekeeping / Relays / Mechanisms

Instrument Processor Board(128K PROM, 512K EEPROM,4MB SRAM, 512MB SDRAM)

Frame Builder 1Custom FPGA / SRAM

Power Supply BoardS

pac

ec

raft

Comm / Mem Board(512 MB Flash)

S/C Power

Spacewire

ICU Block Diagram

Frame Builder 2Custom FPGA / SRAM

To Filter Wheel Stepper Motor

To APS Htr

+3.3V Digital Power

To HPP

(x2)+1.7V ASIC Power

ASIC Substrate Power

Fiber Optic Cables from HPPs

1 PPS

Slow Control

(Spacewire)

ICU Concept (8 slot version)

29.5 cm

2.5 mm

23.2 cm

23.2 cm

ICU Concept• 2.5mm Al chassis for shielding (5 kg)• 3U/6U box, 6 slot backplane (488 g)

– Slot 0: LVPS (500 g, 11.25 W @ 70%)– Slot 1: 3U System Slot, Instrument Processor Board (450 g, 3.55 W)

• Instrument control, telemetry formatting

– Slot 2: 6U Comm/Memory Board (880 g, 3.55 W)– Slot 3: 6U Frame Builder Board 1 (880 g, 6.25 W)– Slot 4: 6U Frame Builder Board 2 (880 g, 6.25 W)– Slot 5: 6U HK / Relay / Mechanism Board (880 g, 6.50 W)– Slot 6: spare

• Total mass: ~ 10.0 kg• Total power: 37.4 W

ICU Concept• Mass (IXO PDD allocation is 26.5 kg, w/

redundancy):– Total mass: 10.0 kg (CBE)– Total redundant mass: 25.9 kg (CBE+30%)

• Power:– ICU Power: 37.4 W (CBE)– Total + 20%: 44.9 W (CBE + 20%)

Summary

• PSU, MIT, and JHU are excited to have a chance to contribute to this mission!

• Interested in ICU:– Power, mechanism control– Frame builder and telemetry formatting– Hardware and software– Joint development by PSU, MIT, JHU

• Note that we also have experience in large thin filters for Chandra (HRC and ACIS)

Backup Slides

Based on IXO WFI / June 2010

Proposed US Contribution to WFI• Based on IXO WFI instrument teaming arrangements• Proposed US contribution: frame builder and event processing

software• PSU: provide high-speed digital framework, high-speed fiber interface to FEE • JHU: frame builder (event recognition)• MIT: flight software (event processing)

• Builds on decades of combined experience in X-ray imaging instruments, including • Murray/SAO-JHU: Einstein HRI, ROSAT HRI, Chandra HRC• Bautz/MIT: ASCA SIS, Chandra ACIS, Suzaku XIS, • Burrows/PSU: Chandra ACIS, Swift XRT

Fiber Optic interface to ICU

www.spacephotonics.com

Fiber Optic interface to ICU

www.spacephotonics.com

Design flexibility, good radiation tolerance, high speed, low power

FEE

ADCADC

ADCADC

ADCADC

ADCADC

FPGAFPGA

FPGAFPGA

FPGAFPGA

FPGAFPGA

CAMERACAMERAFlex cableFlex cable Flex cableFlex cable

Instrument Control

CPUCPU

Frame Builder S/C I/FS/C I/F

Slow Control/ConfigSlow Control/Config

Power Conditioning

H/KH/K

Image Controller / APS Sequencer

Image Controller / APS Sequencer

Controller Power

Controller Power

Heater Power/Con

trol

Heater Power/Con

trol

ASIC PowerASIC Power

Sensor PowerSensor Power

Processor Power

Processor Power

JHUJHU

PSUPSU

ULUL

MITMIT

mechanism controls

mechanism controls

SoftwareSoftware

WFI baseline

ICU

WFI ICU1) CPU = Brain + Slow control2) PSB: low voltage power supplies3) S/C Interface (SpaceWire?)4) Camera Interface (serial optical + SpaceWire?)5) HK: all HK from outside the ICU will be digitized

locally and provided to ICU on the slow control bus6) Heater power / mechanisms

1) Detector temperature control2) Filter stepper motor (if needed)3) any other heaters or mechanisms

7) Frame Builder (JHU)1) Frame buffer2) Event recognition and formatter

8) System Software (PSU/SwRI)1) O/S, drivers, S/C interface, heater control, ...

9) Science Software (MIT/JHU)

+ Fully Redundant B-side

1) CPU = Brain + Slow control2) PSB: low voltage power supplies3) S/C Interface (SpaceWire?)4) Camera Interface (serial optical + SpaceWire?)5) HK: all HK from outside the ICU will be digitized

locally and provided to ICU on the slow control bus6) Heater power / mechanisms

1) Detector temperature control2) Filter stepper motor (if needed)3) any other heaters or mechanisms

7) Frame Builder (JHU)1) Frame buffer2) Event recognition and formatter

8) System Software (PSU/SwRI)1) O/S, drivers, S/C interface, heater control, ...

9) Science Software (MIT/JHU)

+ Fully Redundant B-side

Issues/Questions

Issues/Questions

Issues/Questions