• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 441 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

best practices for INA3221 and INA301 grounding

Giulio Zoppi
Intellectual 645 points
Part Number: INA3221
Other Parts Discussed in Thread: INA301

Hello, 

I am exploiting both INa3221 and INA301 for monitoring two different supplies. 

The latter is used in conjunction with the MCU Microcontroller's ADC.

I got two questions concerning the GND scheme to follow in both cases:

#1- The INA301,  as you can see from the pic, is referred to the  MCU's ANALOG GND. The only doubt is about which GND we should connect  C97 : The regulator's noisy DGND or the clean MCU_AGND?

#2- INA3221 the situation is different because dis device embeds its own ADC.. so do you believe is still necessary connecting its ground to a clean one or we can exploit the regulator's DGND?

thanks for your support.

Regards, 

G.

  • 0
    TI__Mastermind 26335 points

    Hello Giulio,

    Thanks for considering Texas Instruments.  Ideally you want your INA301 and INA3221 to go to as clean of ground as you can manage as a noisy ground would be analogous to a noisy power supply.  Noise on the supply can be translated to the output and may appear even larger for the downstream device that has a clean ground.  Also depending on how much resistance is between your grounds, this might produce an additional offset that may make your load look larger than it is.  Therefore if you have any control routine that kicks in slightly above your normal operating conditions, this offset may cause that routine to trigger prematurely. 

  • 0 in reply to Patrick Simmons
    Intellectual 645 points

    Ciao Patrick,

    thank you for your valuable support.

    We can definitely move everything to the clean ground.

    Regards

    G.