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Rare Bird
28-12-2009, 08:20
in the Maverick Audio DAC i'm using i've located the DAC chip that seems to be a National Semmiconductors LF353N ! i don't know anything about this chip but from experience NS aint that sparkling.

Has anyone had experience with it & offer any recommendation of direct replacements i could try?

Maybe Leo's the man for this

http://www.alldatasheet.com/datasheet-pdf/pdf/8579/NSC/LF353N.html

leo
28-12-2009, 09:54
Hi Andre

The LF353N is a dual jfet input op-amp, it could be used in the dacs output stage or even a servo, depends tbh, we'd have to see the dacs circuit before recommending possible replacements:)

Rare Bird
28-12-2009, 10:06
Cheers Leo
I've mailed em for one.

leo
28-12-2009, 11:36
Loooking at a few pics (second pic in link) as a guess I'd say the op-amps could be some buffer or filter for the analogue input , this dac does have an analogue input doesn't it? if so I wouldn't bother changing the LF353, we'd still have to see a schematic to be sure

The dac chip could be the smd device (also seen in second pic ) which has had its numbering sanded off to try and keep it a secret, it may also be the input receiver ?? , going by the chips package size as a guess I'd say its one of Cirus logics , things like CS4397 and 98 dac and CS841* receiver is a popular choice lately for the dacs found on ebay.
Its possible the dac goes straight to the Tube stage, the CS439* based chips are voltage out dacs so have the op-amps/switching capacitors built inside the chip so don't need any external op-amp I/V, again we need to see the schematic to be sure, either that or some very close up pics of the pcb top and bottom

http://hardforum.com/showthread.php?p=1035054016#post1035054016