I think its time to go for discrete. If you observe all the companies who cannot afford to manufacture smaller quantities are finally discontinuing the parts. Its better to go with discrete. I have tried pcm1704 and when the discrete version of the dac is built it outperformed by a big margin.
lot prefer to use discrete opamps as well. I think its better to do that way.
The semi conductor resistor always has got some noise issues unlike the discrete ones.
lot prefer to use discrete opamps as well. I think its better to do that way.
The semi conductor resistor always has got some noise issues unlike the discrete ones.
I thought buying 12x LME49600 and 4x-8x of about 6 varieties of op amps was stocking up!
You're welcome, and never a doubt in my mind. I noticed the same odd matchings in a few places as you mentioned. Outside of my comment that a lot of the higher performance parts in this line are SOIC, which means we DIYaudio'ers need to up our soldering skills (but benefit from lower lead inductance!), there is no reason you can't find a suitable replacement. The rest is some kind of bizarre specmanship.
I agree agree with both.
I have a posted project here on the forum that uses OPA827's. I ordered 15 of them from Arrow in this last go around in fact, along with a bunch of OPA140s and OPA2140s. The OPA1642 is what Quant Asylum uses in the (very good) QA400 distortion analyzer.I'm actually using BUF634's in yet another posted project here (2 looped with an OPA2140), simply becuase I needed a tab to attach heat sinks, othewise I would have used a LME49600. I have LME49990's and LME49600's in posted projects here, as do other folks like opc with his "Wire" headamp series. But I do agree with jackinnj, it is a personal taste thing on the BUF634/LME49600. Some folks prefer one or the other after listening experiences. And some folks prefer discrete buffers.
This particular part discontinuation/fab-closing seems to smack of Not Invented Here, ie the National stuff. I guess that is why this one irritates me to some extent, I've been through that party before at a couple of large corporations over the years. Buy smaller company - squeeze all you can our of their existing products but don't grow anything - jettison the remains a few years later. Lol, I'm not expecting any TI reply, just venting steam.
I see you are a TI employee. A big thanks for chipping in here with the feedback.
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Drop and mop. I pull it off and I'm legally blind with gorilla hands.
It's a colossal pain, though. I avoid SM parts as much as possibly can. Breakout boards are available to make it easier. Adapter, Breakout Boards | Prototyping Products | DigiKey
Wikipedia on wafer sizes:
A quick Google search also turned up a PCN from last year saying
More discussion here.
...
6" wafers are 150 mm. So that fab/line would seem to be a bit long in the tooth now. Not like it would matter much for audio, but it does for economics.
A quick Google search also turned up a PCN from last year saying
So they've got an 8" (200 mm) line there as well.
More discussion here.
Just to jump in...
Analog opamps can be subtituted by several others or there is a way around to solve a problem in a repair.
Sometimes it's an impossible repair and the unit is scrapped.
But; all you ucontroller guys...
Wat happens with your projects or even the units of reputed manufacturers when they break down after a decade or so.
Who is able to reprogram that digital stuf if the source code is lost?
Who is capable of replacing a digital chip when it is no longer in production?
Things to think about.
Wouldn't it be better to build analog again and with discrete components?
As a customer I like to pay a lot more if I know it can be repaired after twenty years.
And as a technician, I do not have to tell my customers that their five year old unit is ready for scrap because of lacking parts...
I know I sound old fashion, but "wasn't father allways right"?
Analog opamps can be subtituted by several others or there is a way around to solve a problem in a repair.
Sometimes it's an impossible repair and the unit is scrapped.
But; all you ucontroller guys...
Wat happens with your projects or even the units of reputed manufacturers when they break down after a decade or so.
Who is able to reprogram that digital stuf if the source code is lost?
Who is capable of replacing a digital chip when it is no longer in production?
Things to think about.
Wouldn't it be better to build analog again and with discrete components?
As a customer I like to pay a lot more if I know it can be repaired after twenty years.
And as a technician, I do not have to tell my customers that their five year old unit is ready for scrap because of lacking parts...
I know I sound old fashion, but "wasn't father allways right"?
Tell me one thing I have built amps using lme49810 811 etc and found they sound excellent for me as we have compared with many highend discrete amplifiers but the LME parts sounded better than the discrete design. Including the Bryston and parasound. But there is one thing to be considered in IC there are pros and cons
Pros: miniatured and price is well managed and as well as faster production.
TI VIP 30 process used in LME has got very precise npn and pnp transistor matched inside so precise that its in the order of 0.1% which in discrete will take alot to match the transistors. Now thats the plus point and another point to consider is the trace inductance which is very negligible in the TI non hybrid ICs
cons: Arent the resistors used in it are semiconductor based? arent they worse than the conventional discrete resistors?
The LME parts most of them are of BJT input based have anybody compared a Jfet input based amp with a BJT input based? Im trying now if it works it would be great I wouldnt be going with LME anymore but I have a strong feeling that many says even a discrete opamp beats opa627.
So I think discrete will rule as the parts will be available for quiet long.
Yep, indeed.
Then we know we can repair and enjoy our loved and money costing equipment.
We will talk again when your 3 years old multichannel AV amp filled with ucontrollers will break down and the repair shop will inform you that it's total loss due to the unavailablitiy of the used chips (from any source).
I speak from experiance as technician. Great (very sad) feeling that is...
Then we know we can repair and enjoy our loved and money costing equipment.
We will talk again when your 3 years old multichannel AV amp filled with ucontrollers will break down and the repair shop will inform you that it's total loss due to the unavailablitiy of the used chips (from any source).
I speak from experiance as technician. Great (very sad) feeling that is...
Yeah. and the computer you are posting this on and the phone you make calls with and the internet. Microprocessors are everywhere, and guess what, they are amazingly reliable. My 14 year old car has half a dozen, all still working. Oh and spares are still available.
Spares are always available from somewhere if you are willing to pay for them. Am I upset that the Z80 is not still available in a DIL package from mouser? Of course not.
Do cheap brands build in obsolescence? Of course they do. Been a fact of life for a very long time. Welcome to planet earth
Spares are always available from somewhere if you are willing to pay for them. Am I upset that the Z80 is not still available in a DIL package from mouser? Of course not.
Do cheap brands build in obsolescence? Of course they do. Been a fact of life for a very long time. Welcome to planet earth
I repeat:
We will talk again when your 3 years old multichannel AV amp filled with ucontrollers will break down and the repair shop will inform you that it's total loss due to the unavailablitiy of the used chips (from any source).
I speak from experiance as technician. Great (very sad) feeling that is...
And I'm not talking of cheap brands. MAJOR brands...
Welcome to the repair world...
We will talk again when your 3 years old multichannel AV amp filled with ucontrollers will break down and the repair shop will inform you that it's total loss due to the unavailablitiy of the used chips (from any source).
I speak from experiance as technician. Great (very sad) feeling that is...
And I'm not talking of cheap brands. MAJOR brands...
Welcome to the repair world...
Its never the uprocessor. (unless we are talking a known manufacturing stock fault on a specific item)
I speak as a former bench tech and workshop supervisor with many years experience.
Welcome to my repair world... when a tech wants to order a uP, I say... look a little harder for the fault first
I speak as a former bench tech and workshop supervisor with many years experience.
Welcome to my repair world... when a tech wants to order a uP, I say... look a little harder for the fault first
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