I use two isolated DC-DC converter in parallel from 24V
- One TDN 3-2411WISM (single output) to create 5V for the "digital world" followed by LDO to create 3V3 and GND for the VDD (+Vout) and VSS(-Vout) of my microcontroller (STM32).
- One TDN 5-2422WISM (dual output) to create -12V (-Vout), +12V (+Vout) and AGND (Com.) for the "analog world" followed by low noise linear LDO to create -3V3 and 3V3 for opamp amplifier chain and for VDDA and VSSA of my microcontroller (STM32)
So, I got two ground plan AGND and GND, I wonder:
- It is ok to use isolated DC-DC in this case?
- Do I need to connect the two ground plan AGND and GND (in one point)?
- Can I connect the two ground plan AGND and GND nearby the VDDA pin of the STM32, it is judicious?