• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 80 subscribers
  • Views 352 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.

MSP430F6436: MSP430F6436 power supply inrush current

Conor
Guru 14850 points

Part Number: MSP430F6436

Hi, 
When the power is applied to the MSP430F6436, an inrush current of about 30mA flows. I would like to reduce this inrush current to 10mA.

Q1
When I use the minimum capacitor value recommended for the MCU power supply, the current consumption at startup is about 30mA. Is this normal operation?

■ Yellow waveform: Current consumption
■ Pink waveform: Vcc

Q2
Approximately how much current should be consumed by the Msp430F6436 itself immediately after startup?

Thanks,

Conor

  • 0
    Guru 43785 points

    The MCU probably has little inrush since it should be held in reset. (Though you don't show the reset circuit.)

    With all that capacitance, there is no surprise that you have a large current at turn-on, especially if those are good capacitors with low ESR.

    You have two choices:

    Slow down the rise of Vdd.

    Put in a parallel RL network to limit the current.

**Attention** This is a public forum