Lansdale ResponseMr. David Robinson
Defense Supply Center Columbus
3990 East Broad Street
Columbus, Ohio 43212-1152
Dear Mr. Robinson:
SUBJECT: Response to Testing of GEM Devices Memo of 24 Oct. 2002
Lansdale Semiconductor Inc. performed electrical evaluation of the GEM devices against the original parts, which were supplied by Lansdale in order to evaluate the GEM parts behavioral compatibility to the original parts. The test data was forwarded to the DSCC Gem Program office on 07 October 2002. Other than electrical differences, a number of other errors were found during a review of the GEM products. The following information is being provided to the GEM program office:
1) M38510/30201BCA (54LS40) - GEM product received has a MIL-PRF-38535 "Q" compliance mark, however, there is no "J" certification mark on the product. The Certificate of Compliance supplied by Sarnoff with the product states that the product is in accordance to MIL-STD-883, 1.2.1. If the Certificate of Compliance is correct, the product should have a "C" certification mark not a "Q". The electrical testing of the GEM device shows that it meets the specification requirements, however, there are some behavioral compatibility issues with Vol, Ios, Iccl, Tphl, and Tplh. Vol and Tphl when graphed over temperature appear to operate inversely to the original devices.
2) M38510/02206BDA (54H103) - GEM product received has a MIL-PRF-38535 "Q" compliance mark, however, there is no "J" certification mark on the product. The Certificate of Compliance supplied by Sarnoff with the product states that the product is in accordance to MIL-STD-883, 1.2.1. If the Certificate of Compliance is correct, the product should have a "C" certification mark not a "Q". The GEM parts are packaged in an "A" package 1⁄4" X 1⁄4" Spider lead flat pack, however, the part number defines the package as a "D" package 1⁄4" X 3/8"axial lead flat package. The functional characteristics of the GEM parts are different and required a modification to the electrical test program for IOS testing. The GEM parts need to be preconditioned to bring them to the correct logic state prior to test. This preconditioning is not required by the original device design, which naturally returns to the correct logic state. Although not disallowed by the device specification, there is no mention of this preconditioning requirement. The electrical testing of the GEM devices show that they meet the specification requirements, however, there are some behavioral compatability issues with Vol, Iil1, Iil2, Iih1, Iih3, Iih5, Ios, Icc, Tphl1a, Tphl1b, Tphl2. Again Vol and some of the Propagation delay testing when graphed over temperature appear to operate inversely to the original devices.
3) 351-7495-012 (529) - The GEM devices were tested to the original generic device specification, because this is what the original manufacturer (Motorola) did. When the electrical test parameters of the SCD are compared to the generic device specification, all of the test parameters are met or exceeded by the generic device so no new test program was generated. When electrically tested to the generic device specification, the GEM parts showed significant Hysteresis which caused them to fail Voo, Vo1 parameters of the standard device. These parameters are unspecified in the SCD but are inherent to the original device design. The GEM program office stated that these parts have been insertion tested and qualified by the Air Force. Were the GEM devices fully operational tested in the application? Are there other applications that use this NSN? Were these parts operational tested in those applications?
4) B77T0137-0123 (54181) - Page one of the SCD states "Inactive for new design and procurement after 02 Aug. 1988. For BT77T0137-0123 use M38510/01101BJX per M38510/011 (see 6.1.1)", Paragraph 6.1.1 of the SCD states "Military equivalent. The following Military parts are designated as superseding parts to this drawing". When a device specification is "Superseded", all manufacturing and testing revert to the new document in this case M38510/011. The definition of "superseded" was verified by DSCC-VQ audit personnel at the time of Lansdale's QML re-certification audit.
When testing the GEM devices to the requirements of the M38510/01101BJA, the GEM devices failed Icex, Vol, Iil2, Tphl3, Tplh4, Tphl5, Tphl13.
The GEM program stated, "It is unclear from the GTL raw data how the measured delays fail to meet the M38510 minimum delay requirements". Review of the raw data shows Tplh4 and Tphl3 at low temperature show failing test results, test numbers 141, 143, and 239 for all GEM devices, <7 Ns minimum.
The GEM program stated that: " The GTL Vol measurement does not correlate with the GEM characterization data for devices with the same date codes. It is possible that in performing the ICEX measurement (not required by the SCD or included in the TI generic data sheet), the GEM outputs may have been damaged by applying test conditions beyond the scope of the target specification". The ICEX test is a requirement of the superseding document M38510/011. All of the original parts tested passed Vol after ICEX testing. Is the inherent robustness of the GEM devices in question or the methodology of test? Lansdale would be happy to perform a correlation study with the GEM program office on these parts.
The GEM Program Office stated: "The device was successfully insertion tested by the Air Force and qualified in the intended application(s)". Was full operational testing of the system performed? Was full operational testing performed in the other applications of this device?
The GEM program states: "The GEM Program designed the device to the referenced SCD per the customers request and not to M38510/01101. The GEM device was never intended or advertised to be a compliant MIL device". The SCD is superceded by the M38510/01101 and should not have been used.
5) M38510/06302BEA (10525) - GEM product received has a MIL-PRF-38535 "Q" compliance mark, however there is no "J" certification mark on the product. The Certificate of Compliance supplied by Sarnoff with the product states that the product is in accordance to MIL-STD-883, 1.2.1. If the Certificate of Compliance is correct, the product should have a "C" certification mark not a "Q".
Lansdale has provided electronic copy of all the test data to the GEM program office. Three of the five GEM devices marginally fail Voth4 at low temperature, Min limit is 2.5V Serial number 6 = 2.35, 7 = 2.33, 9 = 2.16. One GEM device Serial number 10 had invalid readings for Votl4 caused by input sensitivity of the GEM devices. Serial numbers 9 and 10 failed TTHL13 @ 25 Deg.C. Max limit is 3.3 NS 9 = 5.594, 10 = 5.581. Serial numbers 9 and 10 failed TTLH4 @ 125 Deg.C. Max Limit 5.3 NS, 9 = 6.407, 10 = 6.564. Serial numbers 9 and 10 failed TTLH5 @ 125 Deg.C. Max Limit 5.3 NS, 9 = 6.52, 10 = 6.364. Serial numbers 9 and 10 failed TTLH12 @ 125 Deg.C. Max Limit 5.3 NS, 9 = 5.894, 10 = 6.051. Serial numbers 6,7,9,10 failed TTLH13 @ 125 Deg.C. Max Limit is 5.3 NS, 6 = 5.312, 7 = 5.312, 9 = 6.654, 10 = 6.877. Serial number 9 failed TTHL13 @ 125 Deg.C. Max Limit is 5.3 NS. 9 = 5.738. The electrical test program and test hardware have been reviewed by DSCC-VQ and verified to meet the requirements of the M38510/06302 specification. Upon notification DSCC-VQ had samples of the GEM parts tested at their own Laboratory and verified Lansdale's test results. Lansdale has supplied both failing GEM parts and passing Lansdale parts to DSCC-VQ for test correlation and review. There is concern that the GEM contractors reverse engineering noted transition times of the Motorola parts were out of specification limits. Did they use fully compliant Motorola devices for this reverse engineering? The comments that the continuity testing may have damaged the GEM
parts does not speak well for the inherent robustness in comparison to the original parts.
NOTE: For all five of the device comparisons made, the original Lansdale parts passed all electrical testing.
SUMMARY: Lansdale believes that the use of GEM emulated devices, (where no other original design devices are available), to support an individual weapon system application under a new part number and NSN is truly a benefit to both the weapon system and the taxpayer.
Lansdale electrically tested the GEM parts to the specification in the same manner as the original device manufacturer would have tested them and shown significant deviations from the original devices. The test data is not erroneous as verified by the DSCC-VQ review of Lansdale's testing of the M38510/06302BEA and confirmation of our test results from DSCC's internal test lab.
The review of the GEM parts showed that three of the five device types were either incorrectly marked or shipped with the wrong C of C. Two of the five parts, although meeting the electrical requirements of the specification, showed significant behavioral compatability issues to the original
device. Two of the devices when tested to the M38510/ specifications as defined by the part number (or superceded SCD), failed to meet the electrical requirements. One part, although marked M38510/02206BDA, is in fact a M38510/02206BAA (it is in the incorrect package). These GEM
devices were selected at random from the excess inventory listed at the GEM web site as being indicative of the normal GEM products.
Lansdale, along with the SIA-GPC, JEDEC JC-13.2 committee and the GEIA G-12 committee, has stated in a written position letter that the GEM emulations do not meet the Form, Fit and Function requirements and must have a different part number and NSN's to segregate them from the original devices. Using the same part number with a different technology is in effect making system design changes on all of the weapon systems that utilize the parts. These design changes without the benefit of engineering review and verification and full operational testing could have catastrophic effects and must stop immediately.
If you need any additional information, please contact me at (602) 438-0123,
Lansdale Semiconductor Inc.