I am using a AD7366 / 7367 while connected to a DSPIC33 at 3.3V
I am measuring the 3.3v BUS AT 4v, REMOVING ad7366 from PCB resolve issue
desoldering Vdrive from PCB (pin 2) also solves issue
using diode check on pin 2 to pin 3 shows a diode drop of about .6V while vdrive is disconnected from PCB
is this IC in fact compatible with a Vdrive lower than DVcc
Can you tell me a little bit more about what hardware you are using for the AD7366? Are you using the customer evaluation board or are you soldering it onto the prototyping area of the dsPIC Ready board or similar? If you are using some other board can you share the schematic for that hardware so that I can review it?
As stated in the PIN description VDRIVE is independent of AVCC and DVCC.
I am the engineer, custom PCB.
just was re-reviewing fig20 in datasheet, i think I have REFSEL tied to 5V, and not 3.3V, but need to check sch. files when back in office tomorrow, likely that is the issue, would explain what I am seeing while testing PCB
Well, must have been an off day during Sch design, REFSEL infact on 5Vdc, and not 3.3.
little pcb surgery and issue resolved
Glad everything worked out. Please do let us know if you have any need of further assistance.