As I noted upstream they appear to be only for non-selected devices. HP was always designing right to the limits of technology and the way they did that was a lot of selection on the production line or on the vendor lines.Īre you saying that the cross refs that HP published in Bench Briefs were bogus? I have never had a problem replacing an HP part with a JEDEC part when it was listed in a Bench Briefs cross-ref. HP did wonderful designs that pushed the state of the art and the way they did in many places was to select the hell out of parts. The Sphere list will get you close in most cases and may get something to work. A lot of this old gear is getting fixed to function but not to meet the original specs. I have repaired quite a few late 60's HP transistorized test equipment trying to use the Sphere list and ended up having to select from a few dozen parts to get one that would work in the circuit and meet specs. HP was always designing right to the limits of technology and the way they did that was a lot of selection on the production line or on the vendor lines. JEDEC numbers were only good for really simple non critical things like a low frequency switch or simple amplifier. My Siliconix book lists hundreds of JFETS that came from a dozen or so Siliconix processes.Ī common 2N3904 from five different companies would be quite different so many times I had to spec a 2N3904 from Fairchild with a set of needed specs far more restricted than the JEDEC. Trying to design a VHF oscillator with a 2N Jfet is next to impossible because the critical parameters will vary too much from process to process. I used a lot of FET's from Rich's Siliconix and I always went by process number and a list of selected parameters to prevent purchasing from bringing in stuff from other vendors that would vary too much. National supplied hundreds of JEDEC numbers from 40 transistor processes and so did Motorola and many other companies. For a 2N3904 we had 13 part numbers all selected for some set of critical parameters.Īs a design engineer for 50 years the JEDEC numbers were next to useless. We had 7 internal part numbers for an MPSA-64 and that was a Motorola process. At my company it was pretty much the same. I worked for many years with engineers from both Tek and HP and they all told me that over 50 % of the semiconductors were selected in some way. The mobile version now includes a Buy-Now button that connects directly to our e-commerce division New 2022 PC VersionĬlick here to download your free Android versionĬlick here to download your free iPhone versionĭon't forget, you can now order popular components on-line from NTEPartsDirect.Many of the parts on that list are listed like MPSa 64-5 the Motorola part is MPSA-64 the dash 5 is a selected part. Search hundreds of thousands of devices such as semiconductors, relays, resistors, switches, potentiometers, trimmers, fuses, RF connectors, disc thermostats, terminal blocks, terminals and connectors, and more! Search results include links to easy-to-read, datasheet PDFs. This new version contains many new NTE devices, including all semiconductors added since the last update. With thousands of new parts added, you are now able to cross references over 700,000 industry part numbers. NTE Electronics has released the latest version of their popular cross reference software program, QUICKCross™. The industry's most comprehensive electronic cross reference software available today!
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