Sanken SAP15 , 5 pin Darlingtons

N_Cook

unread,

Oct 27, 2016, 10:18:40 AM10/27/16

to

With the built in temp comp diodes, 1 silicon in the N type and 5
Schotky in the P and mirror-reversed pinning .
Owner put a short across one speaker line, magic smoke but other channel
is normal. Internal emitter resistor .22R of the p type is now not .22R.
I intend removing both , of the failed channel , to check out of
circuit, but anyone jumpered in an external .2R in these circumstances
and no further problems from cracked die etc as this R is part of the die?
The datasheet I think , in fractured English, says the thermal safe
operating over-current zone, for the built in .22R is deliberately
lower than the Darlington itself. Anyone ever disentangled the "English"
referring to deliberately? destroying the internal R so as to use an
external emitter R,or is it just referring to doubling-up ?
datasheet
http://pdf1.alldatasheet.com/datasheet-pdf/view/38213/SANKEN/SAP15/+2732WUOYLI.OcU.utw+/datasheet.pdf

Tim Schwartz

unread,

Oct 27, 2016, 1:14:57 PM10/27/16

to

Hello Nigel,

What amp are these in? I know Arcam used them in several products,
such as the A65/75 series. I night have a good PDF of the data sheet if
you need it. The pinout is different on the SAP15-N (NPN) and the
SAP15-P (PNP)

Regards,
Tim Schwartz
Bristol Electronics

Trevor Wilson

unread,

Oct 27, 2016, 5:50:35 PM10/27/16

to

**I did once in a client's amp, to see what would happen. It worked
fine, but I decided to fit new devices to be certain. These Sanken
things are horrible. Sanken has a nasty track record of releasing
devices, then ceasing production after a few years. After which,
substitutes can be either difficult or impossible to obtain. Give me a
standard 3 terminal transistor every day. I'm presently working on a
1975 vintage Accuphase, which will accept modern replacement devices
quite nicely. In 10 years, those Sanken things will be unavailable and
the units that they're fitted to will be boat anchors. I advise anyone
who will listen to avoid products that use Sanken devices for that reason.

--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

Sjouke Burry

unread,

Oct 27, 2016, 5:57:05 PM10/27/16

to

"alldatasheet.com currently unavailable" GRRRRRR

Phil Allison

unread,

Oct 27, 2016, 9:47:24 PM10/27/16

to

N_Cook wrote:
>
>
> With the built in temp comp diodes, 1 silicon in the N type and 5
> Schotky in the P and mirror-reversed pinning .
> Owner put a short across one speaker line, magic smoke but other channel
> is normal. Internal emitter resistor .22R of the p type is now not .22R.
> I intend removing both , of the failed channel , to check out of
> circuit, but anyone jumpered in an external .2R in these circumstances
> and no further problems from cracked die etc as this R is part of the die?
>

** The 0.22 ohm is not part of the die, but a separate thick film resistor as stated in the Sanken data.

> The datasheet I think , in fractured English, says the thermal safe
> operating over-current zone, for the built in .22R is deliberately
> lower than the Darlington itself.
>

** The max current rating of the 0.22ohm is somewhat less than the Darlington itself - but this is not deliberate, just a practical limitation. If the internal resistor has failed, the Darlington may still be OK.

Designers can use an external WW resistor if needed, or add a current limiter circuit that protects the inbuilt one.

I have seen a lot of these devices used in powered speakers made by dB Technologies - their "Opera" series and others.

The "English" in the app notes is bloody dreadful.

.... Phil

N_Cook

unread,

Oct 28, 2016, 3:19:18 AM10/28/16

to

After removing , it became obvious low ohmic C-E, so bang goes that
idea. Perhaps 120V,12A standard pDarlington, with external .2R and 5 SMD
Shottky diodes RTV'd on the top, rather than expensive old-stock SAP15.
Cambridge A5 amp, made in DRC = The Congo ?

legg

unread,

Oct 28, 2016, 9:16:06 AM10/28/16

to

http://pdf1.alldatasheet.com/datasheet-pdf/view/38213/SANKEN/SAP15.html

Chuck

unread,

Oct 28, 2016, 9:26:59 AM10/28/16

to

Does anyone remember the Sanken output IC that JVC used in its
integrated amplifiers that had the exact same number as used by other
manufactuers but when replaced by any IC not sold by JVC there was
huge notch distortion? I spent quite some time on the first one that I
repaired. After the ICs were no longer available from JVC, I found by
adding external resistors that the distortion could be eliminated.

I had an Accuphase E-202 amp and still have the service manual
somewhere if this happens to be the amp you are working on and you
need a schematic.

Phil Allison

unread,

Oct 28, 2016, 9:37:35 AM10/28/16

to

Nutcase Kook wrote:
>
>
> After removing , it became obvious low ohmic C-E, so bang goes that
> idea. Perhaps 120V,12A standard pDarlington, with external .2R and 5 SMD
> Shottky diodes RTV'd on the top, rather than expensive old-stock SAP15.
> Cambridge A5 amp, made in DRC = The Congo ?
>

** ROTFL !!

https://www.avforums.com/threads/cambridge-audio-a5-any-owners-views.867584/

" Made under license in PRC "

PRC = People's Republic of China, established in 1949 by Mao Zedung.

No jungle monkeys involved ....

.... Phil