• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 31 subscribers
  • Views 158 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.

MSPM0L1227: Acceptable minimum frequency for sysosc

Ryuuichi machida
Guru 13320 points

Part Number: MSPM0L1227
Other Parts Discussed in Thread: MSP430FR5869

Hi,

I would like to confirm acceptable minimum frequency for sysosc of MSPM0L1227.
As a comparison, there is following spec on datasheet of MSP430FR5869.
image.png
This shows user can input approx 0 MHz and use as system clock.
On the other hand, according to datasheet and TRM of L1227, there is following spec.
image.png
image.png
From above, it seems that user can NOT set system clock lower than 4MHz.

Q1, Is my understanding correct ?
Q2, If above is "yes", is there any other M0 series which accept lower than 4MHz ?
we would like to realize lowest power consumption as possible as we can like MSP430.

Best Regards,

  • 0
    TI__Mastermind 41850 points

    Yes, for the internal high speed clock source  SYSOSC, it's frequency can't be lower than 4MHz, but MCLK used by CPU, it can lower than 4MHz, for example you can use the LFCLK as MCLK's clock source. 

  • 0 in reply to Gary Gao
    Guru 13320 points

    Hello,

    Thank you for your reply.

    >it can lower than 4MHz, for example you can use the LFCLK as MCLK's clock source.
    When user use "LFCLK" as CPUCLK, it seems that user can set only 32.768kHz. Is it impossible to apply other frequency like 1MHz which is defined in MSP430 datasheet ?


    And, I have one additional question.

    Question2 : If user use 4MHz as cpuclk using sysclk, which voltage can be applied to Vdd ?
    According to datasheet, this device accept Vdd range from 1.62 to 3.6V.
    However, I'm not sure "min Vdd vs cpu frequency" information. For instance, I think when user use 32MHz, Vdd=1.62 do NOT accept.

    Best Regards,

  • 0 in reply to Ryuuichi machida
    TI__Mastermind 41850 points
    Ryuuichi machida said:
    When user use "LFCLK" as CPUCLK, it seems that user can set only 32.768kHz. Is it impossible to apply other frequency like 1MHz which is defined in MSP430 datasheet ?

    No, it just can used to 32k

    Ryuuichi machida said:
    Question2 : If user use 4MHz as cpuclk using sysclk, which voltage can be applied to Vdd ?
    According to datasheet, this device accept Vdd range from 1.62 to 3.6V.
    However, I'm not sure "min Vdd vs cpu frequency" information. For instance, I think when user use 32MHz, Vdd=1.62 do NOT accept

    For MSPM0 do not have this limitation, the device can run 4MHz at 1.62v

  • 0 in reply to Gary Gao
    Guru 13320 points

    Hi,

    Thank you for your reply.
    >For MSPM0 do not have this limitation, the device can run 4MHz at 1.62v
    Did you mean that user can use 32MHz at 1.62V as well ?

    Best Regards,

  • 0 in reply to Ryuuichi machida
    TI__Mastermind 41850 points
    Ryuuichi machida said:
    Did you mean that user can use 32MHz at 1.62V as well ?

    Yes