STK2040 Amp

[KenP]

I pulled one of these chips out of an old yamaha receiver. On the front is written stk2040 stereo power amplifer,only problem is I can't find a schematic or pinout for the chip. Does anyone have any info on it?

Thanks

[halojoy]

Originally posted by KenP
I pulled one of these chips out of an old yamaha receiver. On the front is written stk2040 stereo power amplifer,only problem is I can't find a schematic or pinout for the chip. Does anyone have any info on it?
Thanks

STK made good Power Amp IC.
It should not be impossible to find achematics on the web.
I have seen several threads here at forum,
where initiated discussions were about STK chips.

Wait a little. They will come and give you datasheets.

I searched on "STK" here at diyaudio
Thread with 94 posts!
STK chips

/halo - have good hopes for info on STK2040

[Netlist]

Originally posted by KenP
I pulled one of these chips out of an old yamaha receiver. On the front is written stk2040 stereo power amplifer,only problem is I can't find a schematic or pinout for the chip. Does anyone have any info on it?

Thanks

Hi KenP
http://www.datadart.com/commercesql/...=4341208.88150
is a database from almost all STK's except the 2040

http://matthieu.benoit.free.fr/sourcing.htm is a huge list of company's who provide datasheets. If you have the patience and time you can search it...
Can you provide the type number from the Yamaha receiver?

/Hugo - Thinks STK2040 is OEM-made for Yamaha.

[KenP]

The receiver was a yamaha r-500. I've found many types of stk chips on diyaudio and while searching the web but never a 2040. If they were propiatory to yamaha would there be any published specs?

[Netlist]

When looking at the BACK of the receiver, is there no more than
r-500?

/Hugo - Can't find r-500 receiver despite Halo's hope

[KenP]

I scrapped the rest of the receiver. I bought it on ebay as non working and just used the knobs so far in my esp amp and preamp project. The transformer still works and I'm hoping the chips will be working so I can use them in a home theater sub. ebay auction yamaha r-500 Here is the url for the ebay auction in the description it only says r-500 and I can't remember if there was anything else on the chassis (scrapped long ago). BTW there was another chip in receiver that I just found while looking through everything from it it's labelled stk3042 III.

[Netlist]

You say you bought it as 'non working'.
Hmmm, most of the amps or receivers with STK's who come in for repair have their STK's broken.

Testing an STK is not easy if you don’t have a datasheet, so for the 2040 I think there's little hope.

The 3042 is easy to find on the net so you could give that one a try. http://www.datadart.com/al/sanyo/Stk3042.pdf and
http://www.datadart.com/al/sanyo/Stk3042II.pdf . I think the 3042III must be pretty much the same.

You can do a lot of nice ohmic measurements with the help of the schematic here.
The gif is from a 3062. Same but more power.
That's about all I have.

Sony used it in the STRGX511 and STRGX590.
Maybe someone has a schematic from those amps?

/Hugo

[Netlist]

Oops, forgot the Gif;

[KenP]

Thanks for the help, I guess I'll give up on it then

[SVI2004A]

mmm Being a STK20 series id say its a 16 pin symmetrical pinout device
id also say approx 3rd pin in on each side more than likely goes to spkrs
ill list pinout of STK 20*8

1 (16) +sig in
2 (15) +V
3 (14) OUTPUT
4 (13) -V
5 (12) - sig in
6 (11) PROT
7 (10) PROT
8 (9) GND

it would help me alot if you could give me ideas on the PCB layout
ie... where + & - V rails go, spkr conns etc (find which pins connect to theese basic lines)

- i hope this is of some help, Baily