SSM2142 Balanced Line Driver

Has anyone had experience using this part?
I'm considering using it in a new design insted of a design using 6ea 5532's wired as a transformerless output.

http://www.analog.com/en/prod/0%2C2877%2CSSM2142%2C00.html

I've also looked at the "THAT CORP" equalivent but it's not available yet.

http://www.thatcorp.com/1420desc.html

I like the idea that it's laser trimmed and all of the opamps maintain the same temperature profile being in the same package. The output swing is about the same as 2 opamps, common mode spec looks good ect.
Any comments??

RonL
http://www.nashaudio.com

I have used it with some success, and I have one on my audio generator to drive balanced lines. As you sweep up past about 25 kHz the sine wave is no longer sinish anymore, just the slew rate of the device. Other than that it works fine. I popped one once, but only because I accidentally plugged it into a phantom source.

pleasantly suprised with the ones on the o/p of my 9K clone, very hard, if not impossible to discern any difference between the unbalanced out of the pre and with the balanced driver. This was on my workshop rig though, haven't done any studio work.

Pin-compatible with the Burr-Brown OPA134 if you like to try different flavours... the Burr Brown has 50Ω current limiting resistors internal from what I understand. I use the 2142 quite a bit these days, it's easy and moderately reliable as long as you don't shove phantom at it's backside... :shock:

Keef

Well, it looks like I will be the sole dissenting voice.

The 2142 has a peculiar problem where it will latch up and eventually burn out if the supply rails come up unevenly.... I've been through too many of them!

There is no need for a balanced output stage as long as you are feeding a balanced input stage and the source impedances are the same on pin 2 and pin 3.

Hi,

About the SSM2142, I figure the time has come to ask a question that's in my head for quite while now:

Anyone observed or had problems in practice with rising THD @ low levels ?
Note my concern is only based on an article I read, giving quite bad THD-performance-graphs for lower levels (I should scan & post).
The datasheet of the '2142 gives only performance figures @ 10Vrms, but it looks like THD-performance is quite a lot worse for those lower signal levels - as of course often observed for 'output stages'.

Maybe the multi-5534-approach gives better results...

Clintrubber: -That sounds like a crossover distortion issue: easily tested of course... perhaps even remediable with some current-sources, though that rather gets away from the original promise of "one-chip-problem-solver!)

Zmix: -You say "if the power rails don't come up evenly" -I can't see how at all. -I recently made a circuit involving four of them (posted in the drawing board a couple of weeks ago) which used an outboard PSU, connected through a 4-pin XLR. Owing to at-hand components and a hurried build, I had several problems including a wrongly-wired 4-pin (by an assistant!) a negative regulator that failed to come up 75% of the time (same problem as Jakob's post at the old -now defunct- site where if the positive half comes up forst the negative regulator latches up) and a couple of other problems...

Anyhow, the upshot was that all four 2142's still work fine and I'm pretty willing to bet that if I put them all on my bench supply and fiddle with the way in which the rails come up, and I'd be very surprised if I burned anything up... I think that it might have been something else. For sure, the 2142's will bo ballistic if you shove phantom where the sun don't shine, and for that reason I included specific protection measures in the "OB-1" board for balancing the SSL 9k preamp output. I bet that your real problem was an output/loading issue.

Keith

From the old place

SSM2142 output offset
http://216.239.59.104/search?q=cache:NQ7X__3KZaQJ:www.recording.org/modules.php%3Fname%3DForums%26file%3Dviewtopic%26t%3D18466+ssm2142+site://recording.org&hl=en

Elberg, Kev, Keith and others on 2142s vs 5532s
http://216.239.59.104/search?q=cache:tdFgjDlgFPUJ:recording.org/modules.php%3Fname%3DForums%26file%3Dviewtopic%26t%3D18872+2142++site://recording.org&hl=en

http://www.groupdiy.com/index.php?topic=7902

about the problems with these IC's and phantom..

Clintrubber: -That sounds like a crossover distortion issue: easily tested of course... perhaps even remediable with some current-sources, though that rather gets away from the original promise of "one-chip-problem-solver!)

Click to expand...

Sure, it'll be x-over. FWIW, I need to get the scanner out tonight anyway, so I'll post graphs.
I don't remember exactly how bad it got, but since these parts are used so often it'll often also be at less than full signal. So if there really was an issue then it'll have been brought up before.

Regards,

Peter

[quote author="SSLtech"]Pin-compatible with the Burr-Brown OPA134 if you like to try different flavours... the Burr Brown has 50Ω current limiting resistors internal from what I understand. I use the 2142 quite a bit these days, it's easy and moderately reliable as long as you don't shove phantom at it's backside... :shock:

Keef[/quote]

OPA 134 comes up as an ordinary opamp.
http://focus.ti.com/lit/ds/symlink/opa134.pdf

Which BB part did you mean?

JH.

It's this one, the DRV134:

http://focus.ti.com/docs/prod/folders/print/drv134.html

There's also the DRV135:

The DRV134 is available in 8-pin DIP and SOL-16
surface-mount packages. The DRV135 comes in a
space-saving SO-8 surface-mount package.

Click to expand...

Regards,

Peter

[quote author="rlaury"]Has anyone had experience using this part?
I'm considering using it in a new design insted of a design using 6ea 5532's wired as a transformerless output.

http://www.analog.com/en/prod/0%2C2877%2CSSM2142%2C00.html
[/quote]

I've used a pair of these once, to add balanced outputs to my VCS3 clone. I run it from +12V / -9V there, and it clips rather early and unpleasant. (I should attenuate the input to the driver some day, but so far I've just been lazy and using th eunbalanced output.)

I thought about using these to balance my soundcard - mixer connections. But so far I'v held back because the chips are rather expensive. Selecting precisely matched resistors for a discrete solution would be ok to me.

So my question is just th eother way round: Are these drivers, built from discrete opamps, as good as the SSM part? I'm mostly asking about stability at capacitive loads, and other parasitic effects. Is there a circuit you can recommend from practice, driving long cables, for this floathing balanced output function? Which circuit would you recommend, and which opamps? Will it work with 5532's, for instance?

JH.

[quote author="clintrubber"]It's this one, the DRV134:

http://focus.ti.com/docs/prod/folders/print/drv134.html

There's also the DRV135:

The DRV134 is available in 8-pin DIP and SOL-16
surface-mount packages. The DRV135 comes in a
space-saving SO-8 surface-mount package.

Click to expand...

Regards,

Peter[/quote]

Thanks!

JH.

I thought about using these to balance my soundcard - mixer connections. But so far I'v held back because the chips are rather expensive.

Click to expand...

You need 8, correct ? (EWS88MT). If you want, then I guess you only need to buy ~2, since you can get free samples from TI & AD. :thumb:

I thought about using these to balance my soundcard - mixer connections.

Click to expand...

Indecent proposal :wink: :
http://www.thomann.de/behringer_di800_ultradi_pro_prodinfo.html
EU74.

[quote author="clintrubber"]

I thought about using these to balance my soundcard - mixer connections. But so far I'v held back because the chips are rather expensive.

Click to expand...

You need 8, correct ? (EWS88MT). If you want, then I guess you only need to buy ~2, since you can get free samples from TI & AD. :thumb:[/quote]

It's a Phase 88, but yes, 8 channels in and out.
Ordering samples privately somehow never works, and I don't want to do it via my employer.

JH.

[quote author="clintrubber"]

I thought about using these to balance my soundcard - mixer connections.

Click to expand...

Indecent proposal :wink: :
http://www.thomann.de/behringer_di800_ultradi_pro_prodinfo.html
EU74.[/quote]

It's tempting! :wink:

But if it hums as badly as the Composer I used to have from the same company, it's not so tempting anymore.

JH.

But of course you're right, that total thing costs as much as a decent hum-free diy psu *alone*, or the ssm chips alone, or the enclosure and mechanical harware alone ... :shock:

JH.

It uses '4580 opamps I thought I read.

BTW, their DI4000 has half the channels, but TX-outs, also for EU74:
http://www.groupdiy.com/index.php?topic=7929
I'm wondering if anyone has used these already. I guess circuitwise they're alike to their 1-ch. standalone DI-boxes.