If you are using SDRAM1 platform with SDRAM1 Adapter – you will face some problem testing PC100 & PC133 Modules.
The SDRAM1 was design for testing 66Mhz or PC66 SDIMM only – using this platform to test PC100 or PC133 DIMMs will yield incorrect test results.
To test PC133/PC100 SDRAM DIMM – you need to use EK-SDRAM2-Platform with EK-SDRAM2-Adapter or EK-SDRAM3-Platform with EK-SDRAM3-Adapter to correctly identify a PC133/PC100 DIMM module. The SDRAM2 Platform can be also used to test PC66 SDIMM.
To test PC133 SDRAM DIMM – you need to use the latest SDRAM3 platform and SDRAM3 Adapter to correctly identify a PC133 DIMM module. The SDRAM3 Platform can be also used to test PC100 & PC66 SDIMM.
For DRAM module testing , if the Eureka fail the following test :
Walk Address Failure - checks and detect open/short on address pins and bad address decoder.
Walk Data Failure - checks and detect open/short on data bits
Marching Failure – checks and detect bad cells and decoder interaction problem
Checkerboard Failure – checks and detect for bad cells, decoder interaction problem.
Leakage Failure ( Optional) – checks and detect one and shorts on all control an data pins, and memory cell leaks.
Pre-heat Test Failure– checks and detects reliability during chip warming –up.
Voltage bouncing test – check and detect modules with noise related problem
Loop Test Failure– to simulate module burn-in situation
For SDRAM Testing:
In addition to the above patterns, the following are found only in SDRAM testing mode :
Burst test failure - checks for faulty chip that fail to read and write during consecutive clock cycles.
Chip select test - checks for assembly shorts and open on the CS pins
DQM failure test - checks for shorts and open on the SDRAM chip input and output masking ability
WP fail test - check for module that is PC-100 Intel compliance.
*If your module is a known good module that works on the computer- but fail on the Eureka, it might be caused by a worn out test socket , defective test adapter, or a Calibration is due.
Contact CST for an RMA number if you have tried all the above.
Occasionally you might chance upon certain modules that the tester identify as eg 64ns instead of 60ns, this can be caused by several factors:
Signal degradation due to the chip loading effect on the SIMM or DIMM module, the result only happen to one or two types of module, typically with a sizable amount of chips mounted on board.
If the timing is consistently high irregardless of type of module, then contact CST for RMA number to have your tester checked out.
* If the “SPD data test” is selected in the test pattern , the tester will perform a SPD read and write comparison after functional test.
* If the original SPD data store in the tester buffer does not match the programmed SPD – the tester will fail “ SPD Data Test”. Ensure the SPD write compare enable function is enable from the” SPD Edit function”.
* Certain SDRAM DIMM modules are assembled with preprogrammed SPD EEPROM which are software write protected, you will not be able to reprogrammed this type of EEPROM again. Check with your supplier if you are not sure.
* Solder shorts on the SPD pins could also result in “Fail SPD Test”, perform a visual inspection on the SPD EEPROM leads.
* A defective EEPROM which is incapable of data retention – will also fail “SPD data test” . Try rewriting the SPD several times and it still fail- replace a new SPD EEPROM chip.