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-FM TESTSTAND #2

LAT Quality Assurance

Performance & Safety Assurance LAT NCR Report

The following Nonconformance Report # 00177 was submitted on 09/21/04 15:45:32

 

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 FM Teststand 02

Supplier: 

Location: 

Drawing/Rev #:   

Lot/Heat #: 

Serial #: 

Test Procedure/Rev #: 

 
Description of Nonconformance:  The problem as described by NRL: "The problem with FM02 is an inconsistency between energy range bits and ADC readout value on Cable Controller 1. Intermittently, energy bits indicate LEX8 or HEX8 but ADC value appears to be LEX1 or HEX1." The TEM/TPS unit was received by SLAC. The problem was found using SLACs ASIC screening software, and concluded this error occurred because the ASICs were not prescreened. It was agreed that cable controller 1 was in error, and was found that the U6, GCCC 1 ASIC on JC1 had errors in the Data Fifo Test. Bit 13 was stuck on low in memory locations 20 and 21. The ASIC was replaced and passed all performance testing.
       

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:  
The problem was found using latest SLACs ASIC screening software, and concluded this error occurred because the ASICs were not prescreened. It was agreed that cable controller 1 was in error, and was found that the U6, ASIC GCCC1 on JC1 had errors in the Data FIFO Test. Bit 13 was stuck on low in memory locations 20 and 21. The ASIC was replaced and passed all performance testing requirements per documents LAT-TD-03415 and LAT-TD-01652.

The TEM/TPS unit was returned to NRL.

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

Root Cause: 
ASICS were not prescreened.

Action taken to Preclude Recurrence of Discrepancy: 
All flight ASICS are prescreened and passed 168 hours B/I at +85 degree C.