I was under the impression that both parts were interchangeable. Is that usually correct? The dual jfets would be used in input stages of various audio preamplifiers and amplifiers. Just wanted to get some overall opinions on which are better in these sorts of applications.
I have always hated the sort of poorly defined part swapping thing that is unique to audio.
You always need to consider a part in the context of the surrounding circuitry, otherwise you are asking for voodoo not engineering.
Look at the data sheet, look at the circuit you want to use the part in, maybe do some modelling, maybe you need to change a few other parts to put the alternate component into the correct operating region, sometimes the difference is huge, sometimes the parts are directly interchangeable, it depends on the surrounding circuitry, to do otherwise is voodoo not engineering.
Even for something 'simple' like "What is the best replacement for a 5532A", without knowing the rest of the circuit, all you can really say is "another 5532A", and small signal jfets are not anything like as interchangeable as jellybean opamps.
Sorry, but the only answer here is to run the numbers for your particular application.
Regards, Dan.
You always need to consider a part in the context of the surrounding circuitry, otherwise you are asking for voodoo not engineering.
Look at the data sheet, look at the circuit you want to use the part in, maybe do some modelling, maybe you need to change a few other parts to put the alternate component into the correct operating region, sometimes the difference is huge, sometimes the parts are directly interchangeable, it depends on the surrounding circuitry, to do otherwise is voodoo not engineering.
Even for something 'simple' like "What is the best replacement for a 5532A", without knowing the rest of the circuit, all you can really say is "another 5532A", and small signal jfets are not anything like as interchangeable as jellybean opamps.
Sorry, but the only answer here is to run the numbers for your particular application.
Regards, Dan.
LS844 may help you replacement for 2N5566/2N5565.
For LSK389, try LSK489, datasheet show lower Ciss.
For LSK389, try LSK489, datasheet show lower Ciss.
I don't know about you but I've got a lot more 2N5566s than LS dual JFETs in my parts bin. They were purchased new, from DigiKey, in a previous century. No you can't have any.
Mark,
The longer you hang onto them the more they are worth to someone maybe someday.
Any plans for them?
I'll trade you some lsk389B for 2n5566, next time I'am in San Jose that is.
P.S. thx for quasimodo, I have mine running, a great addition to my TE.
2n5566 have much higher noise at the 10Hz test frequency.
I guess lsk389 with it higher input C is better for low source Z, see Bob Cordell's lsk489 app note, a good read.
The longer you hang onto them the more they are worth to someone maybe someday.
Any plans for them?
I'll trade you some lsk389B for 2n5566, next time I'am in San Jose that is.
P.S. thx for quasimodo, I have mine running, a great addition to my TE.
2n5566 have much higher noise at the 10Hz test frequency.
I guess lsk389 with it higher input C is better for low source Z, see Bob Cordell's lsk489 app note, a good read.
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I have some BFQ15 and SU2369A. For the first one I've found datasheet, for the second one I can't. Any experience with those dual fets?
I've read Cordell's notes, but still think that the LSK389 is a superior part to LSK489. LSK489 does not appear to be a drop in for 2N5564 either.
I guess I should clarify my OP. I'm not really interested in which part looks better on paper. I'm more interested in real world experiences. Which dual jfet sounds better in similar designs?
What do you look for in the data sheet. Of cause the obvious are the gm, capacitance, offset matching etc.
I do not know this answer but I would recommend that you design your pcb to accommodate both types. Your opinion and others may differ.
I could also recommend BF862, but of course you should hand match them.
Hello,
Are you sure that the LS844 is the best choice ?
On Linear web site they recommend LS5911
http://www.linearsystems.com/assets/media/file/datasheets/LS5911_5912_5912C.pdf
Thanks