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MSP430FR6879: Reset pin processing and power supply voltage

Part Number: MSP430FR6879
Other Parts Discussed in Thread: MSP-FET

Hi,

Question1

The document stated that "BOR resets when the change in power supply voltage is ± 0.05 V / μs or more."

Does the BOR reset due to a sudden power rise have any other effect?

  

Question2

"When using MSP-FET, connect 47kΩ and 2.2uF CR reset circuit to the RST terminal," the document stated.

If MSP-FET is not used, can the MSP430 start up normally by increasing the constant of the CR reset circuit (eg 470kΩ, 0.1uF)?

Please let me know if you have any problems.

Thanks,

 

Koki

  • Question2

    "When using MSP-FET, connect 47kΩ and 2.2uF CR reset circuit to the RST terminal," the document stated.

    If MSP-FET is not used, can the MSP430 start up normally by increasing the constant of the CR reset circuit (eg 470kΩ, 0.1uF)?

    Please let me know if you have any problems.

    FRAM device as SBW target does not need any resistor / capacitor combination on RESET pin (there is internal pull up, and capacitor is only disturbing factor because switching SBW bidirectional logic signal is fighting with it). TI recommendation is 47k and 1nF (not uF). If device is not used in setup with SBW master than any  capacitor / resistor combination (that guarantee correct start-up in noisy environment) can be used.

  • Hey Koki,

    1) No, the BOR resets don't have any other effect besides just an unintended reset. 

    2)  Zrno is correct about the reset pin, the recommended time constants are mostly important during JTAG programming.

    Thanks,

    JD  

  • Hi, 

    Thank you politely.

    If my customer does not need SBW access, the data sheet states that a capacitor up to 10nF can be used.

    Please tell me the connectable range of the pull-up resistor and pulldown capacitor.

    I am wondering how much the time constant can be increased or decreased.

    Thanks,

    Koki

  • Hi,JD

    Do you have any update?

    Thanks

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