Silent & noisy grounds on a RIAA preamp

[carlmart]

To prevent too big DC @ your output I recommend replace LT1792 with 800 uV DC offset to OPA192 with 5 uV offset [ I have only 1.5 uV with it - see https://www.patreon.com/posts/64958853 ].

That preamp looks very much like the discrete I was going to build, cloning a Luxman 5C50 RIAA preamp a late friend of mine had.

It is not advantage LT1792 vs OPA192 because OPA192 is also with JFET input 🤓

Is there a Pspice or LTspice model for the OPA192 available anywhere?

 

[Nick Sukhov]

Is there a Pspice or LTspice model for the OPA192 available anywhere?

Spice models see here https://www.patreon.com/posts/spice-modeli-i-v-58962178

 

[carlmart]

How do I open that site in English?

 

[carlmart]

I have to pay to open the models! No deal, sorry!

 

[mason_f8]

I believe the OPA192 is a MOS input, not a J-FET.
The OPA192 has an R to R input, but it is clearly stated that the Nch operates when VCM approaches +Rail. I believe this is a feature of the enhancement C-MOS.

 

[Mark Tillotson]

Its not necessarily CMOS, just MOS front end. The data sheet never uses "CMOS", "JFET" or "bipolar" in its description, only mentioning the n-channel and p-channel input MOSFETs. But the relatively high output current suggests its internally CMOS. If it were a hybrid device they'd probably mention it, and the presence of both n-FET and p-FET devices strongly implies some sort of CMOS process is used. But they are keeping quiet about it...

CMOS refers to using complementary p- and n-FETs in totem-pole stages.