Hi Simon,
😏
It does (gravity), but the effect of gravity is the same everywhere and the strength of the force does follow the laws of physics.
That was my point.
😏
It does (gravity), but the effect of gravity is the same everywhere and the strength of the force does follow the laws of physics.
That was my point.
Just read the 2nd Edition of Burkhard Vogel's Slopes & Levels. He mentioned that the noise values for a 1990 NE5534 were identical to those of some TDA1034's he had from the 1970-ies. Redesign or not.
Jan
Jan
The OPAx134 is a different type, it's a FET input. So they are optimized for different applications.
Cost or not, you just can't swap them without verifying whether the application allows it.
Jan
Cost or not, you just can't swap them without verifying whether the application allows it.
Jan
I like the graphs of open-loop gain versus frequency in old datasheets. One can see that the compensation has more than one pole.
Ed
Ed
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That's in most opamp data sheets. In fact, if that graph is not in the data sheet (as is the case with many discrete opamps) I won't use the opamp in my designs.
Sometimes the compensation is a bit subtle in the amplitude graph, but obvious in the phase response. OPA1612 for example:
Tom
Signal Network Electronics ( Signetics ) Was doing well in the 60's ironically most those guys came from Fairchild.
And by the late 60's were not doing too well. Think there was maybe 2 or 3 investors that tried saving them.
The investment money basically evaporated. So Phillips took a pretty big risk buying them.
Around 1974/75
The main focus was logic/computers.
Mainly bankers and military were actual buyers before apple and the known others made home computers.
Ironically Fairchild where they came from, was the one dominating the market by the 70's for logic.
National Semi thought they would take on IBM and INTEL and bought Fairchild for the logic tech. Didnt really happen.
Texas Instruments bought National more for Analog domination, everyone kinda gave up trying to win Intlel for logic.
But Fairchild was the dominate logic company, before home computer market.
Another big deal for communication was the phase lock loop, and there is conflicting stories if Fairchild or Signal Networks
was the dominating designer.
Ironically logic and the opamp was mainly supported in early days by military. In a nutshell Error factor correction for radar and weapon servos.
Anybody wanting to argue that Quasi Complementary output sections are " use less junk" try again. 90% target accuracy all Quasi
well into the 90's
The Quasi-Complimentary design was for battlefield robustness since PNP parts weren't as good back then. Also those designers held onto what they knew worked. Military and industrial drives all semiconductor development. Those are the markets you need for success. Audio? An afterthought, tiny market.
I get the sense that if you lost your job in the Silly Con Valley in the 70s or 80s, you just walked across the street to the competitor. Hate your boss? Start your own company! Hate your employees? Buy another company! The industry has matured lots since then.
TI makes lots and lots of NAND gates. They're very good at that. I doubt Intel makes actual logic ICs anymore, but they've certainly done well in the processor world. Unfortunately for them it looks like they're having their lunch slowly eaten by ARM and TSMC. With an ARM chip I can get a high-performance laptop with 18-hour battery life. I doubt an Intel-based laptop will last that long in standby.
Tom
TI makes lots and lots of NAND gates. They're very good at that. I doubt Intel makes actual logic ICs anymore, but they've certainly done well in the processor world. Unfortunately for them it looks like they're having their lunch slowly eaten by ARM and TSMC. With an ARM chip I can get a high-performance laptop with 18-hour battery life. I doubt an Intel-based laptop will last that long in standby.
Tom
The military is very conservative for obvious reasons you stated. I worked as a battery control officer for a HAWK air defense battery in the early 1970-ies. The motor drives that ran the radar antenna positioning systems had push-pull 2 x EL34 output stages. It took me some time before I realized why the techies always wanted to put new tubes in them. The removed ones always disappeared. 😎
Jan
Nice, I was missile programmer for the Lance missile. For me no tubes.
I saw life action of the HAWK and NIKE missiles on Kreta(NAMFI) when I was firing the Lance.
I saw life action of the HAWK and NIKE missiles on Kreta(NAMFI) when I was firing the Lance.
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I recall some bar in Chania. I later switched to the air force. (Verzorging squadron) Repairing TV and videorecorders for the soldiers abroad.
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Motorola and Mullard were strong in PLLs, along with Raytheon. For some reason Signetics were hard to buy in the UK.
Wasn't this around the time Europe had a program to make their own "megabit" ram chips? Philips had a large stake in that.
But semiconductor brand keep buying each other to these days. It can be hard to know who owns who.
Depends, but in the late 60's you could walk in the door with a basic 2 year degree.
Towards the 80's lots of politics, sometimes you did or did not get hired depending on who you worked for.
By the 90's they paid you to not work for other people. Really depends if you were working on classified or public projects.
A lot of trends started moving towards software, lots of fancy houses bought with no hardware experience. Depends
Dont really know, most the engineers I knew were Fairchild / National
Philips was the butt of a lot of jokes around the water cooler, just a pride thing
5532/5534 has a strong background with sound production, music equipment.
Probably what holds my interest to it. Otherwise would have nothing to do with it just from family background.
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Compared with 2005 where National Semiconductor wouldn't hire anyone with less than a Master's degree for a design engineering job. And for good reasons, I might add.
Tom