Re: Jellybean Opamp - was What the h--- TI's Burr Brown parts manufacturing? - was Photodiode case

Phil Hobbs wrote:
Joerg wrote:
Phil Hobbs wrote:
Ecnerwal wrote:
Meanwhile I'm sitting on 20 or so LF455/6/7 which obviously did not survive the intervening 20 years, so I hope I can find the right paper book (I have some stashed here, and some elsewhere), as National does not have the datasheets for those on-line, and I'm not over-fond of the "pay money for data***" people. My op-amp book stops at LF453...
Of course there's also the "do I want to use them at all, if they have been weeded out of the stream" consideration, but I hate to waste things (other than storage space, evidently).


Those were nice parts. I still have some left too...iirc they're in the 1989 data book. I'll look them up and see if I can post the data***--basically they were the LF3xx series with the current limit resistor pinned out separately, so you could use higher current at lower supply voltages.

National did some *weird* stuff in 1988--they came out with about 20 new *hybrid* designs, like the LH4009 buffer. Of course, those lasted about 2 years and went the way of the dodo. I still have some.


They also did some not-so-nice stuff. Brought LH0063 and 0033 buffers to market, excellent parts, used by ATE folks all around the globe, then sent out the funeral notice. Now there is the occasional fist fight among obsolete-parts dealers if a stash shows up somewhere.

You can't blame National too much for those two--they stayed around for 20 years or so, unlike the 1988-89 vintage.

I still have about 25 LH0063Cs. I used those and LH4009s back in the day to test sensor back ends--you record the front end outputs for signals of interest, mainly just-missedits and squeakers-under-the-wire, and store them. To test the back ends, you grab hold of some poor op amp's output with an LH0063 and force it to replay the canned data. Works great. Too bad you can't get them anymore.


You can get good money for those. I bet National could also turn a nice little profit from them if they brought them back. I mean, they don't have to produce them domestically.

The LH0033 was also good but much harder to cool.

BTW I've got a two-pager "advanced notice" about the LF455/6/7 series from the 1988 databook. Let me know the address if you want it emailed. Interestingly, in the 95 book they are gone. Must have been one of the most short-lived opamps ever.

--
Regards, Joerg

http://www.analogconsultants.com/
.