Thank you Calvin for the detailed explanation and the effort you put in it, much appreciated.
Another non directly related question...
I have 2 5V linear power supplies that I would like to use for powering the +\- OPA860, I know the virtual ground method of how to get + and - voltage from 2 power supplies but where do I need to connect the virtual ground point from the joined power supplies in the OPA860 circuit? do I need to connect it to the AGND from the AD1862?
Another non directly related question...
I have 2 5V linear power supplies that I would like to use for powering the +\- OPA860, I know the virtual ground method of how to get + and - voltage from 2 power supplies but where do I need to connect the virtual ground point from the joined power supplies in the OPA860 circuit? do I need to connect it to the AGND from the AD1862?
Hi,
You can simply connect two (independant, two transformers, regulated) supplies in series and connect the joint to agnd.
jauu
Calvin
You can simply connect two (independant, two transformers, regulated) supplies in series and connect the joint to agnd.
jauu
Calvin
Who have compare by listening test this discrete version from Nelson Pass's D1 underHi,
instead of a stacked pair/triple of AD844s (a pair seems the minimum to cope with the +-1mA of DAC current) a single OPA860 or OPA861, which use the same topology as the AD844, may be used.
The OPA861 featuring a OTA only (Operational Transconductance Amplifier), the OPA860 also featuring a integrated Buffer, like the AD844.
If You want to design Your own Buffer something like a diamond made from bipolars is what is typically used in the integrated circuits.
If You want to use the bipolar I-V linked to in my last post You may even use the same bipolars in a diamond buffer.
jauu
Calvin
Here´s a fully dimensioned sim. 😉
https://www.diyaudio.com/community/threads/diy-d1-i-v-stage.181449/
against the integrated versions AD844 resp. OPA860/OPA861 ?