GLAST LAT Project DOE Review, February 18, 2005
Gamma-ray Large
Area Space
Telescope
G. Haller
SLAC haller@slac.stanford.edu
(650) 926-4257
4.1.7 DAQ & FSW V1 1

GLAST LAT Project
• Overview - Production & Testing - Schedule
– TEM/TPS Flight Units
– PDU Flight Units
– GASU Flight Units
– SIU/EPU Flight Units
• Testbed
• Installation & Test Support
• Budget
DOE Review, February 18, 2005
4.1.7 DAQ & FSW V1 2

GLAST LAT Project DOE Review, February 18, 2005
ACD
TKR Front-End Electronics (MCM)
ACD Front-End Electronics (FREE)
CAL Front-End Electronics (AFEE) TKR
–
–
CAL
Global-Trigger/ACD-EM/Signal-Distribution Unit*
Spacecraft Interface
Units (SIU)*
Storage Interface
Board (SIB):
Spacecraft interface, control & telemetry
LAT control CPU
–
LAT Communication
Board (LCB): LAT command and data interface empty empty empty
EPU-1
SIU*
SIU*
GASU*
Power Dist. Unit*
EPU-3 empty empty
EPU-2
16 Tower Electronics Modules & Tower
Power Supplies
3 Event-Processor Units (EPU) (2 + 1 spare)
–
Event processing CPU
– LAT Communication Board
– SIB
Power-Distribution Unit (PDU)*
–
Spacecraft interface, power
– LAT power distribution
– LAT health monitoring
4.1.7 DAQ & FSW
* Primary & Secondary Units shown in one chassis
V1 3

GLAST LAT Project DOE Review, February 18, 2005
TKR not shown
LAT GRID with 16 CAL/TEM/TPS Modules
CAL
4.1.7 DAQ & FSW V1
TEM
TPS
4

GLAST LAT Project DOE Review, February 18, 2005
• Tower Electronics Module: Main DAQ module, one on each tower
– Controls and reads out data from TKR
MCM and CAL AFEE front-end electronics
– Assembles CAL and TKR event fragments to tower event
•
Tower Power Supply module, one on each tower
– Input 28V
–
Generates low-noise voltages for
• TKR (2.65V analog, 2.65V Digital)
• CAL (3.3V analog, 3.3V digital)
•
TEM (3.3V and 2.5V digital)
• TKR Bias (20V-140V programmable)
• CAL (20V to 90V programmable)
Tower
Electronics
Module (TEM) before coating/staking
TEM
Tower Power Supply
(TPS) before coating/staking
4.1.7 DAQ & FSW V1
Shown upside-down TPS
5

GLAST LAT Project DOE Review, February 18, 2005
• Status
– Three Flight Tower-Electronics Modules/Tower Power Supplies received
• Fully assembled
•
Thermal-cycled
• Vibration tested (one of them to qualification levels)
• One unit finished thermal-vacuum testing
• One unit in thermal-vacuum testing
• Both units finished EMI/EMC testing
•
No issues/problems
– Balance of 19 TEM/TPS in surface-mount assembly at vendor
• Schedule
– 2/17/05 First TEM/TPS to I&T
– 2/25/05 Second TEM/TPS to I&T
– 4/1/05 Third TEM/TPS to I&T
– 4/22/05 Fourth TEM/TPS to I&T
• One week lag between delivery of consecutive assemblies
– 7/26/05 Last TEM/TPS to I&T
4.1.7 DAQ & FSW V1 6

GLAST LAT Project DOE Review, February 18, 2005
GASU
4.1.7 DAQ & FSW V1
PDU
7

GLAST LAT Project DOE Review, February 18, 2005
EM PDU enclosure with primary/redundant PDU circuit cards, no coating/staking
• Primary and Redundant Circuits in one Enclosure
– Receives Primary and Redundant 28-V from spacecraft
–
Each, primary and redundant PDU can select between primary and redundant spacecraft power
– Filters 28V
– Turns on/off 28V to 16 towers and 3 EPU’s under program control
–
Protects PDU and down-stream circuits from overcurrent and under-voltage
• Over-current via poly-switches
• Under-voltage via custom circuit in each poweron branch
–
Receives command/clock from GASU
–
Digitizes voltages/temperatures from > 150 sources
•
Includes temperatures from radiators, GRID; used for thermal control
– Reads back data to SIU via GASU
– Provides PDU DAQ voltage and temperature analog data to spacecraft for monitoring
4.1.7 DAQ & FSW V1 8

GLAST LAT Project DOE Review, February 18, 2005
• Status
– Design/documentation complete
– Enclosures fabricated
– All parts received (except recalled International Rectifier regulator, due end of February)
– Assembly contract awarded
– All parts kitted and audited by assembly vendor
– Assembly started
• Schedule for Flight Unit
– 5/15/05 Precoat PDU assembly ready for electrical test
– 5/30/05 Complete assembly ready for environmental test
– 7/1/05 Flight PDU to I&T
4.1.7 DAQ & FSW V1 9

GLAST LAT Project
• Primary and Redundant Circuits in one Enclosure
– Contains two types of circuit card assemblies
•
GASU Power Supply CCA
•
GASU DAQ Board CCA
–
GASU Power Supply
•
Receives 28-V supply voltages for
– Primary and redundant DAQ board, generates 3.3V and 2.5v
– ACD FREE cards
» Filtering for 28-V
» 3.3V regulation
– GASU DAQ Board
• Contains 9 FPGA’s
•
Includes Command Response Unit, Fan-out and fanin of commanding to 16 TEMs, PDU, EPU’s,
ACD
• Includes Global Trigger Logic
• Includes LAT Event-Builder Logic
•
Includes command/control/read-back for ACD sub-system
• Includes power-control for ACD FREE Boards
DOE Review, February 18, 2005
PDU enclosure with primary/redundant PDU circuit cards, no coating/staking
4.1.7 DAQ & FSW V1 10

GLAST LAT Project DOE Review, February 18, 2005
• Status
– Design/documentation complete
– Enclosures fabricated
– All components/parts received
– Assembly contract awarded
– Parts being kitted
– Flight assembly to start 3/10/05
• Schedule for Flight Unit
– 5/20/05 Precoat GASU assembly ready for electrical test
– 6/10/05 Complete assembly ready for environmental test
– 7/13/05 Flight GASU to I&T
4.1.7 DAQ & FSW V1 11

GLAST LAT Project
• Spacecraft Interface Unit (SIU)
• Event Processor Unit (EPU)
• Difference is boot code loaded into RAD750 CPU
LCB Enclosure
Power-Supply
DOE Review, February 18, 2005
Backplane
CPU
SIB
4.1.7 DAQ & FSW V1 12

GLAST LAT Project DOE Review, February 18, 2005
• Status
– Design/documentation complete
– Enclosures fabricated
– All components/parts received except BAE RAD750 CPU
• Uses recalled International Rectifier regulator
• Boards to be sent back to BAE
• Reworked boards expected 3 weeks after they receive components; June 05
– Assembly contract out for RFP
•
Schedule
– 6/1/05 Precoat cCPI boards ready for electrical test
– 7/28/05 Complete assembly ready for environmental test
– 8/19/05 First Flight SIU/EPU to I&T
– 8/24/05 Second flight SIU/EPU to I&T
– 8/27/05 Third flight SIU/EPU to I&T
– 8/30/05 Fourth flight SIU/EPU to I&T
– 9/2/05 Last flight SIU/EPU to I&T
4.1.7 DAQ & FSW V1 13

GLAST LAT Project DOE Review, February 18, 2005
• Testbed
– Upgrade of engineering modules to reflect flight designs
– Scheduled over next 6 months
– Labor to support upgrade
– Labor to support testing of electronics and flight software using data generated via front-end simulator boards
– Labor to support test-stands for flight electronics qualification and acceptance testing
• I&T Support
– Design/fabrication/testing of virtual spacecraft simulator for
I&T
– Support for integration and testing of DAQ modules on instrument
4.1.7 DAQ & FSW V1 14

GLAST LAT Project DOE Review, February 18, 2005
• Management
– Sub-system manager
– Technical writer
– Support for environmental test
– Travel
– Computer for test-stations (HW & SW) maintenance
– Shipping charges for flight hardware
• EGSE (Electrical Ground Support Equipment)
– Maintenance/repair of test-stations supplied to sub-systems
4.1.7 DAQ & FSW V1 15

GLAST LAT Project
DOE Review, February 18, 2005
4.1.7 DAQ & FSW V1
Explanation:
Dataflow Electronics = TEM/TPS Flight Units
ACD GASU FU & GLT FU = GASU
Power Conditioning = PDU
SIU & LAT Communication Card = SIU
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