Does anyone here have experience with the 2SC3381 dual NPN transistor?
Datasheet:
http://www.datasheetcatalog.com/datasheets_pdf/2/S/C/3/2SC3381.shtml
These are listed in the current WES catalogue and are only a few dollars each:
www.wescomponents.com
The datasheet doesn’t specify fT or the inter-electrode capacitances between the two devices, which is very high in some (ie MAT** series) monolithic devices.
Anyone ever tested one out? I’d like to buy a tube or two if they are any good.
Datasheet:
http://www.datasheetcatalog.com/datasheets_pdf/2/S/C/3/2SC3381.shtml
These are listed in the current WES catalogue and are only a few dollars each:
www.wescomponents.com
The datasheet doesn’t specify fT or the inter-electrode capacitances between the two devices, which is very high in some (ie MAT** series) monolithic devices.
Anyone ever tested one out? I’d like to buy a tube or two if they are any good.
vynuhl.addict said:
I dunno. I think the capacitances are still relevant in those applications too (especially in the LTP current mirror). They may still work rather well as input pairs though (they still have a reasonable noise figure, good Hfe and rather low Cob). It’s the actual capacitance between the two transistors and the substrate that really matters though.
Toshiba developed the A1349/C3381 as cascoding devices for the JFET duallies, the reason why they share the same package.
(Toshiba released the dual-BJT pair not long after the launch of the common substrate JFET couple.)
Froggy jbaudiophile posted an fT of 50MHz on the BT thread a couple of years ago, questionable as the rest of the posted data looked rubbish.
(Toshiba released the dual-BJT pair not long after the launch of the common substrate JFET couple.)
Froggy jbaudiophile posted an fT of 50MHz on the BT thread a couple of years ago, questionable as the rest of the posted data looked rubbish.
linuxguru said:
I'm not interested in tight beta matching (its effects can be nulled out with other means), I'm interested in thermal coupling. I'm considering these things in the input amplifier stages of my hybrid valve power amp designs, which have a DC gain ranging from 500-2000+ and no DC feedback - so thermal drift charachteristics are important (small drift at the input, big offset at the complementary outputs for the push-pull VT grid drive)
These parts are a lot cheaper than an LM394 and a lot more elegant and effective than binding a couple of to-92's together.
A low noise figure is also a plus, IMO, worth the price. The Vce is limited to 36V acording to the 
I've got a bunch of LM3046. I use them for RF (HF band) signal processing stuff. They have a rather low Vce of 15V though, which limits their use a bit.
The SOT363 devices are nice, but limited in the Pdiss department (I also have a bunch of BC847/BC857 which are SOT363 dual's with a lower Vce).
Those THAT devices are nice, but a little pricey and no one I know of in OZ stocks them.
The 2SC3381's are stocked by WES, who also stock the 2SA1352/2SC3416 and 2SC3417 high voltage, high fT, low Cob trannies I need for my VAS's, so I'll just order an bunch of these duallies with my next order and try them out.
Cheers,
Glen
The SOT363 devices are nice, but limited in the Pdiss department (I also have a bunch of BC847/BC857 which are SOT363 dual's with a lower Vce).
Those THAT devices are nice, but a little pricey and no one I know of in OZ stocks them.
The 2SC3381's are stocked by WES, who also stock the 2SA1352/2SC3416 and 2SC3417 high voltage, high fT, low Cob trannies I need for my VAS's, so I'll just order an bunch of these duallies with my next order and try them out.
Cheers,
Glen
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.