DOM MB Diagnosis page
Board ID:
V5-000409
Source:
9/20/04, George
Symptoms:
September 16, Intermittant COLD
September 20 CPLD firmware upgrade failed.
December 1, Returned to dungeon from Software Test lab due to anomylous
behavior
Analyst(s):
Gerald Przybylski
Analysis Procedure(s):
September 16, Change PLD
September 20, Power on: Measure Switching
Power Supply output voltages. 3.3V, 2.5V, and 1.8V all at 0V
December 1, While profiling, at -70C, a myriad of ATWD A
and B problems occurred, traced to missing -3.3V and +6.6V.
Fault condition also evident at -75C, then also at +65C. Fault
finally cleared up, spontaneously, at room temperature.
STF at room temperature.
Touched up soldering of U8.
Root cause:
September 16, Boot race condition
September 20, Power supply chip, U8, failure, or soldering quality poor.
December 1, Faulty output power waveform from U8 observed
intermittantly. The fault is unclear.
Mitigation:
Reload PLD to solve cold boot problem.
Replace U8 to solve power failure
Disposition:
Software Testing, and watch for future malfunctions.
Any Other Information:
Traveler September 16
Traveler September 20
Traveler December 1
Parts