LAT  Electronics, Data Acquisition & Instrument Flight Software

  Subsystem Manager:  Gunther Haller

 

Important: EM2 test-stand hardware components are NOT compatible with hardware supplied for EM1 test-stands. Do not mix TEM/TEM-PS/Transition Card EM1 with EM2 hardware. Hardware for EM2 is marked "EM2" on the TEM, TEM-PS, VME Transition Card and LCB supplied.

Documents:

The documents are in the process of being transferred to the LAT-DOC system for official release, please retrieve them from LATDOC's.

Here are applicable document numbers and selected copies of the documents in the release cycle (use them with caution).

Note that we do not perform impedance/short/open/voltage measurements on all pins, but test functionality of the system. The "safe-to-mate" test is the responsibility of the sub-system.

Calorimeter:

EGSE-CAL-AFEE TESTSTAND #2

LAT Quality Assurance

Performance & Safety Assurance LAT NCR Report

The following Nonconformance Report # 00134 was submitted on 07/14/04 13:41:13

 

Entered by Ludvik, Jeffrey - jsludvik@slac.stanford.edu

 

Found by:  Customer Complaint

Type of Nonconformance:  Minor

Discrepancy Level:  Non-Flight Hardware

Sub-System:  Electronics (ELEC)

Item Description:  EGSE CAL AFEE Teststand #2

Supplier: 

Location: 

Drawing/Rev #:   

Lot/Heat #: 

Serial #: 

Test Procedure/Rev #: 

 
Description of Nonconformance:  NRL was receiving bad data from the TEM/TPS module. TEM/TPS modules of AFEE Teststand #2 were returned to SLAC for repair. ASICs on TEM were not prescreened before loading and the existing software testing did not have complete coverage of all possible problems. A new test was developed that had more coverage and when the unit was tested again the error that NRL found was highlighted by the software. The action taken was that 2 GCCC ASICs were replaced, U3 and U5. Due to test error reporting it was hard to distinguish between the two ASICs so both were replaced. ASIC U3 was found to have a data fifo memory problem. After replacement, TEM/TPS unit completed and passed all performance testing and is being shipped back to NRL.
       

Disposition Area

Defect Code:  050 Electronic/Electrical

Disposition:  Rework 
(Valid  dispositions:  Rework, Repair, Use-as-is, Reclassify, Return to Vendor, Scrap, or Documentation Change)

Disposition Instructions:  
08/09/04 08:13:05 marsh

The ASICS GCCC U3 and U5 were replaced. The newly developed software which has more full coverage was used to test the TEM. The TEM/TPS unit was fully retested and passed all performance testing requirements per documents LAT-TD-03415 and LAT-TD-01652. The unit was sent back to NRL on 7/15/04.
08/09/04 09:55:04 marsh

NCR closure approved by David Nelson, DAQ Engineering, and Y.C. Liew, LAT Quality Engineering (e-mails on file).

Root Cause: 
The ASICS installed in the TEM boards were not prescreened and the existing software did not have complete full coverage testing. The existing software did not have complete full coverage testing. The newly developed software was able to identified ASICS GCCC U3 and U5 had a data FIFO memory problem.

Action taken to Preclude Recurrence of Discrepancy: 
Test software was modfied to ensure a more robust electrical performance test is performed on the boards.