Dynamic Shift Registers - Bitsavers - Trailing-Edge

All designs are verified with a circuit analysis programto assure proper operation_ Worst case signalpaths are checked to see that no signal race conditionsex ist_Circuit layouts are performed using both manualand CAD techniques_ Manual artwork generationis produced on rubylith cut and peel material. TheCAD system bypasses this step entirely and goesdirectly from a digitized layout to lOX recticleseliminating the need for rubylith and intermediatereduction steps. National's photomask generationlaboratory is one of the best equ ipped in theindustry including the Macrodata F EDIS System,the David Mann Pattern Generator, Reticle Generator,and 6-barrel step and repeat camera.TESTINGNational has a number of LSI testers that allowcomplete checkout of structured logic (ROMs,RAMs, shift registers, etc.) and random combinationallogic. The random logic testers are computerprogrammed to test to the customer's input/outputlogic specifications. On-line testers include TeradyneJ259, J277, Macrodata 230-2 LSI tester andMacrodata 100 memory system exercisors.After fabrication, each wafer is checked for thresholdvoltage, breakdown voltage, ox ide ru ptu reand sheet resistivity. The wafer then goes intofunctional test. The logic on each die is thoroughlyexercised. This 100% test of each wafer eliminatesany functional defective die from being packaged.After packaging, all devices are stressed to environmentalextremes. The packaged devices are thenreturned for another functional test. Dependingon the customer's requirement, packages can betested under a variety of environmental conditionsand can be subjected to a burn-in cycle. Full MIL­STD 883 processing is offered on all Nationalcustom and standard MaS devices.QUALITY ASSURANCENational's quality assurance department has a completeand comprehensive qual ity control programwhich effectively controls component parts andvendors at a quality level of functional, workmanshipand dimensional criteria. The QA program alsocovers in-process controls of assembled devices,final electrical test, marking and final shipment ofapproved product. All procedures are documentedat specification control and at respective qualityinspection stations. Weekly and monthly reportsare generated for quick feedback of informationfor corrective action purposes.All inspections are performed to specified internalAQL inspection levels which meet or exceed MI L­STD 883.RELIABILITYThe reliability evaluation program in effect atNational is a continuous monitor on the processstability of assembled devices on extended lifetest. Tests which are performed on a continuousbasis on each process are:(a) High Temperature Operating Life Test (extendedlife)(b) High Temperature Storage Test (extendedlife)MIL-STD 883, which specifies testing proceduresfor integrated circu its, was innovatively handled byNational. The company adopted 883 specs as itsown, rather than to set up one procedure formilitary orders and another for industrial customers.Therefore, there are no dual standards atNational. All devices are given the same qualitycontrol treatment and the company inventoriesdevices with guaranteed 883 specs.All standard devices undergo M I L-STD 883 testing.They are 100% subjected to a temperature cycleper Method 1003 Condition D, fine leak test perMethod 1014 Condition A, Helium 5 x 10- 7 , andgross leak test per Method 1014 Condition C.The company has been informed by the NationalAeronautics and Space Administration that it hasreceived line certification under M I L-M-3851 0, thenew military standard defining acceptable proceduresfor producing devices.A customer may request any special rei processingper Document NSC/0002. The intent of this documentis to provide the user with the ability toprocure any integrated circuit manufactured byNational to any class of M I L-STD 883 processing.PACKAGESNational offers a variety of dual-in-line packages(DIPs), metal cans, flat packs, and specializedpackages. Both ceramic and molded packages areavailable.All packages meet the standard JEDEC registeredoutlines. Lead finishes are available in either goldor tin. The ceramic packages meet a leakage of5 x 10- 7 std cc He/sec leak rate. National's moldedpackages are the most advanced in the industryand afford reliability which rivals the ceramicpackages.FACILITIESIn addition to its 150,000-square foot Santa Clarafacility, National has operations in Connecticut,Singapore, Hong Kong, Scotland, Germany andAustralia totaling over 300,000 square feet. Personnelis presently over 3,000 worldwide.I n Singapore, National completed its 90,000-squarefoot facility prior to fiscal 1971 but assembly andtest functions were substantially expanded duringthe past year. The Hong Kong plant doubled insize and will again expand in 1972. In Europe, testand warehousing facilities in Scotland and WestGermany continued to grow in fiscal 1971 in preparationfor future assembly operations. The establishmentof NS Electronics Pty. in Australia providesthe company with an assembly operation inthat part of the world.(")c:en~o3~ofJ)........r­fJ)227