what is a Signetics NE540H?

And why can´t I find a datasheet for this thing online? :? :?

Oopes, misread that, the 540H is a dual channel audio preamp, thats all I know about it.

adam

No, I think it's an integrated power-amplifier-driver (i.e. most of a power amplifier, excluding output transistors) - and I'm pretty sure that it's a single-channel device.

It was commonly used as high-end headphone driver in the early 80'es, but went out of production some 25years ago (I have a hard time finding parts for our headphoneamps). Some multi-track tape recorder used it as a rec-amp, IIRC (try an arcive search at PSW, Gearslutz).

It is housed in a metal-can housing (around 10 or 12 pins). Also known as the SE540H

The special thing about it is that it tolerates quite high supply voltages (+/-40V?) - which is probably also why it went out of production when chip technology changed into +/-22V technology.

Jakob E.

This chip was discussed quite a bit here or at the 'old place'... must have been at the old place I think. Various friendly people found info & surrounding circuitry was discussed. I'll see what I can dig up.

As Jakob said, it's defin. a single channel device.

FWIW, here's a pic of a TX-driver using it (Ampex):



Regards,

Peter

Some more:










OK, I'm linking to all this since I had it on my upload area already since then. People posted more specs etc, if still needed I can dig for that this weekend.

Bye,

Peter

Thanks, guys!

Yes, if you have a datasheet, that would be great!

[quote author="rafafredd"]Thanks, guys!

Yes, if you have a datasheet, that would be great![/quote]

A complete datasheet didn't turn up, but various people posted info & specs. I have it at home, will post this weekend.

Just curious, where did you find those ICs in and what are you're going to do with them ?
As it turned out they have not really any relevance anymore - for instance a 5534 plus a few discrete BJTs makes you a driver with lower-THD.

Bye,

Peter