Linear Systems Dual Transistors

[jgedde]

The LS312 and LS352 seem like appealing devices for input stages. They have good Hfe, 60V BVCEO and they're matched to boot. Noise is a complete unknown, unfortunately.

The THAT3xx seem great with regard to noise, but are very limited with regard to Hfe and BVCEO.

Has anyone used the LS parts? Any words on whether these should be considered "low noise" parts? They only give a NF spec is of limited value. I'd really like to see a noise density figure for these parts...

Thanks in advance,
John Gedde

[homemodder]

jgedde, I dont know the ls parts, but if you looking for top performance dual try this one, its excellent in all respects, 2sc3067. Cheap too, around a 1.5 dollars.

[sandyK]

The LS352 is supposed to be a replacement for the 2N3811A, (among others) which was a very good device, and used by designers like Erno Borbely. The LS312 is I believe a replacement for the 2N2920 (among others) and also heavily favoured originally.

SandyK

[scott wurcer]

The layout is right on the data sheet, these are small two stripe devices, that coupled with the 3dB noise figure at 10k source resistance does not bode well for these being low noise.

On Hfe, remember low base series resistance and high Hfe are somewhat incompatible. So the lowest noise and really high beta don't go together.