Where have all the Low Noise Transistors Gone?

[gerhard]

Seems great, thanx! For P, this ZXTP2013ZTA ?

I have only tested the NPN. In Art Of Electronics III is a large table.
At least I have bought:
mouser fzt951 sot-223
digikey fzt851ta npn sot-223
npn zxtn25020BFHTA
pnp zxtp25020bfhcT-ND digikey
pnp zxtp2027fta digikey with note 220pV
pnp zxtp25012 sot-89 DK
zxt690bkct npn d-pack
zxtn07012effta DK marked BF=1100
zxtp07012effta sot23 marked high beta

(inspecting my Zetex drawer)

 

[alexopth1512]

You mean table 8.1a (low noise BJTs). Most of them are non SMD but I ll do an exhaustive search. I would prefer LCSC to have them but mouser is fine too

 

[mondogenerator]

What about the quite new zetex ZTX1049A? Any news about these in audio apps?

 

[dreamth]

Its not really new...1051/1055 are complementary.I have some of them all, never used in audio, better suited for resonant converters.

 

[Mark Johnson]

The spice model on Diodes Inc's website is 27 years old:

*ZETEX ZTX1049A Spice Model v1.0 Last Revised 15/6/95 * .MODEL ZTX1049A NPN IS=1.5E-12 NF=1.0 BF=600 IKF=7.5 VAF=100 + ISE=0.9E-13 NE=1.25 NR=1.0 BR=150 IKR=3 VAR=15 + ISC=5.0E-13 NC=1.76 RB=0.1 RE=0.018 RC=0.007 + CJC=136E-12 CJE=550E-12 MJC=0.352 MJE=0.36 + VJC=0.554 VJE=0.726 TF=400E-12 TR=6.9E-9 * *$ *

 

[mondogenerator]

Its not really new...1051/1055 are complementary.I have some of them all, never used in audio, better suited for resonant converters.

Haha...only to me then...

They just seemed attractive, quite low saturation voltage, low voltage (so I assume lower noise), and good current capability (relatively)