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MSP430FR2433: Confirm the specification of "Brownout power-down level"

Guru 24520 points
Part Number: MSP430FR2433
Other Parts Discussed in Thread: MSP430FR5969,

Hi TI Experts,

Please let me confirm the following question.

[Question]
Would you please teach me the specification of "Brownout power-down level"?
I checked the datasheet but I could not find this specification.

Best regards.
Kaka

  • This is specified in table 5-2.

    (And if that 0.1 V value is correct, it might be a better idea to use the supply voltage supervisor.)
  • I have already checked this table. In other device like FR5969 has the table for BOR. So, I think that TI has a specification of BOR.

    Best regards.
    Kaka
  • Hi TIer,

    I am waiting for your kind feedback now. My customer requested to us to add the BOR specification like "Table 5-1. Brownout and Device Reset Power Ramp Requirements" on datasheet of MSP430FR5969.

    Best regards.
    Kaka
  • Hi Kaka,

    As Clemens pointed out the correct table to reference in the MSP430FR2433 datasheet is Table 5-2. We don't have a table equivalent to Table 5-1 of the MSP430FR5969 datasheet. I'll pass this suggestion onto our internal team but I can't provide a time table for when or if the table will be provided.

    Best regards,
    Caleb Overbay
  • Hi Caleb,

    Thank you for your comments.
    We would like to know the voltage range specification of Vvcc_BOR+ and Vvcc_BOR- as you know. According to the datasheet, the minimum BOR voltage will be 0.1V, and the maximum voltage does not defined. And the "VBOR, safe" was explained as below.
    > A safe BOR can be correctly generated only if DVCC drops below this voltage before it rises
    So, does this mean that the device will not happen the BOR until below 0.1V if disabled the SVS function?

    Best regards.
    Kaka
  • Hi Kaka,

    I've reached out to my internal team regarding this question and I'll provide an update when I hear something from them. Thank you for your patience.

    Best regards,
    Caleb Overbay
  • Hi Caleb,

    Thank you for your support.
    I am waiting for your kind feedback.

    Best regards.
    Kaka
  • Hi Kaka,

    I reached out to my internal team and confirmed that no BOR will occur until 0.1V and VCC mus then stay below VSHSH+ for at least tBOR. However, I highly recommend using the SVS. Do you intend to disable the SVS in your application? I'd like to get a better grasp on how you intend to use the information regarding the BOR level.

    Best regards,
    Caleb Overbay
  • Hi Caleb,

    Thank you for your confirming.
    The reason why customer would like to disable the SVS is that they wouldl like to operate the MSP430FR2433 at 1.8V.
    Note: Their application required very low power consumption.
    If SVS is enabled when the MSP430 run on 1.8V after power-up, the SVS will work.

    If you have any questions, please let me know.
    Best regards.
    Kaka
  • Hi Kaka, 

    I strongly recommend the MSP430FR2433 not be used in this fashion. In fact, it can't be. The SVS is enabled by default at power up and has a max power up level of 1.99V. This means that if the voltage during power up is only 1.8V, the device is not guaranteed to be released for operation. This is something that is default during device start-up and cannot be changed. 

    Additionally, the SVS can only be disabled in LPM3 or lower and is active by default in all power modes. This can be seen in section 2.2.2 of the MSP430FR4xx and MSP430FR2xx Family User's Guide.

    So the lowest voltage the MPS430FR2433 can actually operate at is VSVSH- which is 1.86V for this device (Table 5-2 of the MSP430FR2433 datasheet). However, at startup, VCC must still rise above VSVSH+ for the device to be released to proper operation which is 1.99V as previously stated. There is a TI design that uses this approach that can be found here

    Best regards, 
    Caleb Overbay

  • Hi Caleb,

    I know that the SVS high threshold is 1.99V(MAX), so it need to exceed the 2.0V at power-up. After power- up, I think that the SVS can be disabled. Because I confirmed the 1.8V operation with using the MSP430FR5969 LaunchPad. It can be disabled the SVS function during Active mode even though the SVS should be "always" in Table 6-1. Operating Modes on datasheet and it worked well. So, I think that SVS can be disabled during active mode.
    Also, I confirmed this to other E2E post.
    e2e.ti.com/.../631507
    e2e.ti.com/.../631787

    Also, I think that if those MSP430 family could not work on 1.8V, I prefer to that TI should change the device specification on datasheet from "1.8V to 3.6V" to "2.0V to 3.6V"

    Best regards.
    Kaka
  • Hi Kaka,

    The threads you linked to don't confirm that the MSP430FR2433 can be run at 1.8V with the SVS disabled in active mode. In fact, the first E2E post you linked to specifically states that it cannot be turned off in active mode. Also, testing on one MSP430FR5969 launchpad is not enough information to confirm that this would work across all parts.

    Even if you are able to disable the SVS during active mode, you are running the part out of spec. I highly recommend following the procedures used in the TI design I linked to in my previous post.

    Best regards,
    Caleb Overbay
  • Hi Caleb,

    Thank you for your comments.
    So, I think that if those MSP430 family could not work on 1.8V, I prefer to that TI should change the device specification on datasheet from "1.8V to 3.6V" to "2.0V to 3.6V" or "1.86V to 3.6V".

    Best regards.
    Kaka
  • Hi Kaka,

    Thanks for the recommendation. I'll pass this on to our team responsible for our datasheets. Let me know if you have any further questions.

    Best regards,
    Caleb Overbay
  • Hi Caleb,

    Thank you for your support.
    If you will have any updates about datasheet, please let me know.

    Best regards.
    Kaka

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