Timeline for Who is the main manufacturer of jelly bean parts?
Current License: CC BY-SA 4.0
9 events
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| Apr 21 at 17:05 | comment | added | user216912 | This exact thing, the same part number and datasheet so close as to be effectively identical. But imagine you are the sales engineer and the customer's engineer asks,"What makes your '4558 op amp better than (competitor)"? When it's 5 million parts a month, one better have a good answer. Calling that product's manager at the factory, you may be told it's proprietary. You know the competitors' parts have been thoroughly anlyzed, but there can be no hint of an admission of that.. So you don't get a very good answer. The end result is not a haggling over quality of build, but over pricing. | |
| Apr 5 at 11:28 | comment | added | Tim Williams | @imnotarobot DLA -- Defense Logistics Agency..? | |
| Apr 4 at 23:09 | comment | added | imnotarobot | 'Probably, these days, there are few restrictions or limitations on who can make a part, or sell something as a given part number.' - Generally parts sold with mil-spec part numbers are restricted by the DLA in the US. This includes jellybean parts that are manufactured, screened, and qualified to military standards (e.g. JAN2N2222). | |
| Apr 4 at 20:22 | comment | added | Tim Williams | @tsc_chazz Yes, to be clear there are two, well three let's say, American naming systems for those: number-letter(s)-number of familiar types like that, 6L6, 50C5, etc.; numerical designations, usually industrial/PQ types (5881, etc.); and the naming scheme mentioned here. | |
| Apr 4 at 19:52 | comment | added | tsc_chazz | I'll just note that the initial number on vacuum tubes actually is filament voltage - 12AU7A for instance uses a 12.6V filament, split into two 6.3V segments for applications with lots of 6xxx tubes. | |
| Apr 4 at 18:04 | comment | added | Tim Williams | More to the point, the building blocks of op-amps (current sources, diff and gain stages, current limiting, bias generation, etc.) might be patentable, but many structures predate semiconductors even; the long-tailed pair is a staple since the vacuum tube days for example (and, perhaps arguably, going even further back with analogous mechanisms). Novel structures were those only possible with matched junctions, like bandgap reference, exponentiation, RF mixing, etc.. The Gilbert cell is a famous example: patents.google.com/patent/US3689752A/en | |
| Apr 4 at 18:00 | comment | added | Tim Williams | I don't know offhand how many jellybean ICs were patented, but for many functions, it's not too hard to come up with something sufficiently different to avoid IP issues. Mask rights (a type of copyright) are probably the easier issue to encounter, but easily avoided by doing an original tapeout. Much as copying a PCB can be done by scanning it directly (infringes the artwork), or reverse-engineering the design. | |
| Apr 4 at 17:28 | comment | added | Gos | Very interesting. And what happens with the patents and exclusivity? For example, the variants of the NE5532 are because the patent expired and anyone can produce it? Or the many 555 variants, with quite different characteristics. Or anyone can produce a more or less compatible device as far as it is a internal different design? | |
| Apr 4 at 15:46 | history | answered | Tim Williams | CC BY-SA 4.0 |