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
Sanken SAP15 , 5 pin Darlingtons
Oct 27, 2016
4 Replies
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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
"alldatasheet.com currently unavailable" GRRRRRR
** The 0.22 ohm is not part of the die, but a separate thick film resistor as stated in the Sanken data. ** 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
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