• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 81 subscribers
  • Views 426 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TMS320F28388D: Resistor to be connected between VDD and VSS

Sh.Sasaki
Guru 13625 points
Part Number: TMS320F28388D

Hi experts,

The following description is in the data sheet.

Is it necessary to connect this 56ohm resistor?

Since the voltage between VDD and VSS is 3.3V, it always consumes about 60mA when the resistance is 56ohm. My customers want to eliminate this current consumption.
If the device does not use the low power mode, can I leave it unconnected?

Best regards,
Sasaki

  • 0
    TI__Genius 15385 points

    Hi Sasaki,

    There is an error in  your calculation, VDD voltage is 1.2V and not 3.3V. So typical current from VDD to VSS should be ~21mA and not 60mA.

    This requirement is not just for Low Power Mode operation, this is also applicable when device is not running any application code, and PLLCLK to the system is in bypass mode, usually if you run PLLat System Clock and enable it to the system, VDD current will be high enough (>21mA) and in that case you dont need this 56ohm resistor.

    As long as system can guarantee VDD current to be more than 21mA all the time, then 56ohm resistor is not required between VDD and VSS.

    Regards,

    Nirav

  • 0 in reply to Nirav Ginwala
    Guru 13625 points

    Hi Nirav-san,

    Thanks for the detailed explanation.
    I understand the specifications.

    Best regards,
    Sasaki