what will replace the LM394??

Totally by (bad) luck, I found out that National is stopping production of the venerable LM394!!
http://www.national.com/opf/LM/LM394.html#Overview

What will replace in all those 990 type module?

Luc

Analog Devices will unveil their successor to the MAT02, called MAT12 in June.
Keep your fingers crossed that it's a worthy replacement in this circuit...

I wonder if Diodes Inc would also have something... Just a guess without looking at the specs...  But I do know they had matched pairs too...  Digikey's search filtering (and Mouser's too) is sometimes helpful in finding manufactureres of course...

Glad I stocked up on 394's when I found them at the local electronic surplus house a while ago.

To answer a question someone is thinking: no there are no more available from that source; checked the other day.

Linear makes a replacement. I have a few to test atm for a new run of 990 kits.

Ptownkid said:

Linear makes a replacement.

Click to expand...

Last time we looked at those none of them had noise or voltage performance that get close to the LM394/MAT-02. Has anything changed in the meantime?

JDB.
[while I'm sure some of the LIS parts will function in a DOA, anyone who wants a 990 is likely best off waiting for the MAT-12]

Has anything changed in the meantime?

Click to expand...

Not that I'd know about it.

Samuel

Thirty years ago I manufactured transformerless Mike pre's. Used paralell pairs of 2N4403's on both + & - inputs.  I selected them for gain & noise. With the trim control turned all the way to min. gain they would handle +10 db of line level signal. With a mike plugged in you could not hear any thermal noise from the circuit. Without being terminated they were noisy but you do not have the fader open on unused channels.

THD was .003% & the sound was very clean, a great improvement over the mike pre w Beyer xfmr. in early MCI 416 consoles. The best part is that hey only cost pennies apiece.

Take it for what it is worth.

So what are the important parameters that make the lm394 good for this purpose? We know that mismatch and noise are an issue...but with 1000's of choices out there, why can we not find a suitable choice atm?

Ptownkid said:

So what are the important parameters that make the lm394 good for this purpose? We know that mismatch and noise are an issue...

Click to expand...

What do you need to know beyond what was discussed earlier?

Ptownkid said:

but with 1000's of choices out there, why can we not find a suitable choice atm?

Click to expand...

If only there were thousands of (monolithic/coupled) dual transistors.

As for singles, low noise parts have been discussed a lot as well. For ~1mA IC and a few hundred Ohm source impedance you want low rbb, high hFE and low excess noise. NPN candidates would be (from cheap to good) 2N4401, 2SC1815, 2SC2240; for PNP the 2N4403, 2SA970, 2SA1015 or 2SB737s (good luck finding those).

I don't mean to sound like Mr. Grumpy (again), but what are you looking for that hasn't already been mentioned in the BM thread or elsewhere?

JDB.
[and I've finally found some time to get back to the layout of my transistor noise tester/sorter]

Sorry, I meant singles that suited the purpose. Being still fairly green on the important specs of transistors, I'm hoping to learn more. When I look at a datasheet, some things are still greek to me and it's hard to know exactly which are important and which aren't.

I'll go back and read that thread again and try and adsorb more.

thanks grumpy! ;D

Sorry for necroposting and semi ad post: I've came across Philips BCY87 and BCY89 transistor pairs while searching something interesting for my store and got a bunch of:

http://alltransistors.com/pdfdatasheet_philips/bcy87_bcy88_bcy89_cnv_2.pdf

And thought, if there anything else exept MAT02, MAT12, LM394 and dips from THAT and others? Something interesting and useful for projects like SSL9k and similar design we don't know, haven't heard of? What about all these BCY87, 89 and possible others with not so good params as MAT02 but possibly usable? Any experience?

SSM2212 from AD. Also available as PNP.

volker said:

SSM2212 from AD. Also available as PNP.

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looks like a nice part..

JR

Thank you, Volker.
Good, $2.99 price, but no dip, soic and  exposed pad only.
Maybe some vintage parts we missed? MAT12 is good but $17.25 price from analog.com
The idea is that some parts from transistor era are laying around and waiting rebirth.

If anyone remakes the LM394 or similar devices (such as the UA726 internally-temperature-regulated matched pair, used in the Minimoog and another old synth model) I think it would be CoolAudio, owned by Behringer. CoolAudio is already remaking a few of the analog synth CEM/SSM chips that were discontinued decades ago, and has announced that more will be released.

On the other hand, if you believe the announcements and a short video I saw, Behringer has made a clone prototype of the Minimoog (commonly called the "Behringer D"), and I have to wonder what parts it used.

benb said:

If anyone remakes the LM394 or similar devices (such as the UA726 internally-temperature-regulated matched pair, used in the Minimoog and another old synth model) I think it would be CoolAudio, owned by Behringer. CoolAudio is already remaking a few of the analog synth CEM/SSM chips that were discontinued decades ago, and has announced that more will be released.

On the other hand, if you believe the announcements and a short video I saw, Behringer has made a clone prototype of the Minimoog (commonly called the "Behringer D"), and I have to wonder what parts it used.

Click to expand...

Reportedly one of Uli's very first electronic projects was a DIY synth.... Maybe he is doing it as a personal project.

JR 

What about synths - many russian synth have кр159нт1 transistor pair onboard (and others from 159 series)
BTW we've discussed it here https://groupdiy.com/index.php?topic=36426.msg746392#msg746392
Modern AS394 called a sub for LM394.
There are various other russians like Кр198НТ1 (used in Polyvoks synth, 5 matched npn transistors).
I can find all russians relatevly cheap if it's interesting (not only in plastic but in TO-5 too).
Who wants russian synth clone (or russian charachter pre)?  ;D

Has anyone tried any of the Linear systems transistor pairs?

They make a few different types, In pretty much any package you could want. I'm not sure which type (if any) resembles the LM394.

Here's some links to the datasheets;

https://www.trendsetter.com/v/vspfiles/assets/datasheets/Linear%20Integrated%20Systems/LS310,%20LS311,%20LS312,%20LS313_Series.pdf

https://www.trendsetter.com/v/vspfiles/assets/datasheets/Linear%20Integrated%20Systems/LS318_Series.pdf

They also make various concoctions of JFET's, including duals.

They're mostly around the $5 mark, From here

LM394 usually has higher hFE (300-700, with Ic=1mA)
LS313 offers 400-1000 with Ic=10uA
Usually Linear produce very good semiconductors.
BTW is it really important for diffamp to use high hFE transistor pair similar to LM394? In other words can we use something with lower hfe in preamps similar to SSL9k?