INA3221 Pull-up resistor of VPU and PV

masahiko shimizu

Other Parts Discussed in Thread: INA3221

Hi,

Could you tell me about Pull-up resistor of VPU and PV?
Please see the attached file.
In this circuit, PV Pull-up resistor is 100kohm.
and VPU Pull-up resistor is 100kohm.

Is there problem?

I saw Figure 25 of datasheet.
I can not understand Rpu setting method.

Best regards,
Shimizu

INA3221.pptx

over 8 years ago

0 Javier Contreras4 over 8 years ago

TI__Mastermind 28710 points

Shumizu,

VPU is the voltage you would be your logic high. From your schematic I would assume you would want to connect 3.3V directly to the VPU with out a resistor. So shorting across R144 should be your answer.

VPU - Is the high logic level used for all pull-ups. From your schematic I assume 3.3V. This is an input.

PV- Is an output to indicate if the power is valid. From your schematic this is connected correctly.

Please let me know if I can be of any further assistance.

Thanks,

Javier Contreras

0 masahiko shimizu over 8 years ago in reply to Javier Contreras4

Guru 11235 points

Hi Javier,

Thank you for your support.

Could you let me know the reason that I must not connect pull up resistor to VPU, please?

Thanks,
Shimizu

0 Javier Contreras4 over 8 years ago in reply to masahiko shimizu

TI__Mastermind 28710 points

Shimizu,

You should be able connect it with a pull up but there is already a pull-up resistor internal to the part as seen in figure 25.

What is the issue you are seeing?

Regards,
Javier

0 masahiko shimizu over 8 years ago in reply to Javier Contreras4

Guru 11235 points

Hi Javier,

Thank you for your support.
Actually, I confirm customer's schematic.

I tell customer to follow datasheet.

Thanks,
Shimizu

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INA3221 Pull-up resistor of VPU and PV