GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 1 GLAST Large Area Telescope: Electronics, Data Acquisition & Flight Software W.B.S March Monthly Review Gunther Haller (650) Gamma-ray Large Area Space Telescope

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 2 TEM/TPS Status & Schedule Status –Two Flight Tower-Electronics Modules/Tower Power Supplies Both modules delivered to I&T –Qual unit All tests completed, one issue On-board current measurement jumpy under certain conditions –After some experimentation, traced it down to leakage between one of the current monitoring ADC connections and the tracker Bias voltage. –Only see it when bias voltage is increased –Most likely cause: leakage path (assembly issue) between neighboring solder pads were pig-tail is soldered to board –De-mated TEM and TPS, first measurements indicate it is TPS –Next step is opening TPS, but pig-tail is staked so not sure what can visually be observed (need new MRB meeting) Not seen on the two flight boards (A & B), likely cause is assembly issue (cleaning of board?) on qual –Balance of 19 TEM/TPS in assembly at vendor 6 TEM and 4 TPS pre-coat at SLAC, being tested Holding TPS supplies pending resolution of issue, see next slide Schedule –4/17/05 Third to sixth TEM/TPS deliver to SLAC? –4/27/05 Third/Fourth TEM/TPS deliver to I&T –5/6/05 Fifth/Sixth TEM/TPS deliver to I&T –7/26/05 Last TEM/TPS to I&T

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 3 TPS Issue No issue on any of EM supplies Qual supply showed (with load-testboard connected) 100mV-ripple on Cal 3.3V digital, but only if turned on at elevated temperatures –If turned on cold, no issue even at 55C –If turned on warm, issue even at -40C –Turn-on issue Put qual supply on tower with 4 flight-lot (non-flight) CAL AFEE cards and 36 flight-lot (non-flight) TKR MCM cards –No issue up to 75C (highest temp tested) –Additional observation (positive) Communication (configuration/event readout) between TEM/TKR/CAL worked over tested temps from 020C to 75C However temp tests with non-flight TPS but with flight components showed ripple/oscillation at above 65C for TKR 2.5Vdig and 1.5V with above tower –Concern Traced it down to low-ESR of flight-lot capacitors –In process of simulating (non-trivial due to non-existence of accurate converter model) –Measurements in progress look again at stability (network analyzer) –Might have to exchange a resistor to another value, tbd

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 4 PDU Status and Schedule Schedule for proto-flight –4/4/05: unit assembled, pre-coat, to be sent to SLAC for testing –Mid to end April: unit fully assembled, ready for environmental test 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 Tester –Designed analog mux card for TV test, fabricated, is in assembly –Vacuum feed-thru plate on order, due next week –Vibration fixture fabricated

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 5 GASU Status and Schedule Status –Parts kitting Delay due to man-power shortage in kitting Parts just delivered to Aeroflex –Flight assembly was to start 3/20/05, delay (2 weeks) Schedule for proto-flight –Mid April + 2 weeks: unit assembled, pre-coat, ready for test –End April + 2 weeks: unit fully assembled, ready for environmental test 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 Tester –Tester in design/debug –Designed analog mux card for TV test Lots of harness assembly in progress for these cards –Ordered 450-pin feed-thru for chamber, due next week

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 6 SIU/EPU Status and Schedule Status –Parts to be kitted –Board had to be refabricated due to coupon failures (fab now at DDI and Tyco for risk/schedule mitigation) –Also reduced amount of copper in boards to simplify PCI connector assembly –Wave-solder connector assembly looks most promising, but has issues Requires another round of 5 boards to be assembled/analyzed before any flight assembly can occur (vary temperature profile, etc) Can only take place after back-plane boards are back from fab, in 10 days. Schedule –In next 2-3 weeks: assemble another set of PCI boards for testing Analysis at GSFC Decision for flight assembly –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 Tester –In design

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 7 Harness Harness in assembly, priority list with dates on web-page below Hardware/LAT-Harness/lat-harness.htmhttp://www-glast.slac.stanford.edu/Elec_DAQ/DAQ- Hardware/LAT-Harness/lat-harness.htm

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 8 VSC (Virtual Spacecraft Simulator) System Design for VSC complete All non-custom hardware to be for 4 systems on order –Received two sets of GPS and MIL1553 Need to install antenna on roof, make it work, etc –Balance of two sets first week of April SSR hardware interface module‘s complete/tested Need to design interface board for thermistor/RTD measurement function in space-craft (temperatures/voltages usually monitored by SC) VSC –Queing/scheduling/1553 2/3 done –Goal to finish be end of next week Proxy Classes –CCSDS/Networking/Handlers 1/3 done –Goal to finish on 2 weeks FSW Test –Python, 1/3 done –Gola to finish in 2 weeks –FSW test groups has interface and is writing scripts against above Debugging of whole system to be done once all pieces are available 2 VSC‘s for FSW/ISOC/I&T for data-flow lab 2 VSC‘s for I&T to follow

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 9 Issues TPS ripple issue AUSTIN EEPROM DPA problems –Don’t have schedule for new lot yet Qualification of cCPI press-fit connector assembly using solder process Delivery issue with GASU PS Zener protection diode for ACD voltage (April delivery, might eliminate the part) Need to work on closing open FPGA review items

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 10 Level 3 Milestone Count

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 11 Level 3 Milestone List

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 12 Level 3 Milestone List

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 13 Level 3 Milestone List

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 14 Level 3 Milestone List

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 15 Milestone Variance Explanation Schedule Impact Cost Impact Corrective Action –None

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 16 Cost Report

GLAST LAT ProjectMonthly Review, March 30, DAQ & FSWV1 17 FTE Report (DOE/NASA-funded only)