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EVM430-CAPMINI: Change default Wake-Up time on CapMINI EVM430

Part Number: EVM430-CAPMINI

Hi

I am evaluating EVM430 CAPMINI dev board. Board standby current is 6uA. After every 1 minute, CPU wakes up and consumes 410uA, remains in that state for 10s and sleeps again for 1 minute.

I want to disable or change default Wake Up Time. how to do this? Can it remain in sleep mode as long as I want? I did not change any program and it is still out of box application. I changed only connection method to bulk I2C. 

Thank you.

Regards,

 Vishal

  • Hi,

    I played with settings in Captivate Design Center. Here are the settings to disable periodic 1 minute wake up for 10s:

    I tried to optimize current consumption. Average current consumption of board is around 4uA (standby, no touches). Buttons are responsive if they are touched. But I do see that current consumption randomly shoots to 19 to 21uA for very short period of time, and goes back to 4uA. What is the reason behind this?

    With regards,

     Vishal

  • Hi,

    1. I do not advice you disable wakeup interval. Reason is attached.

    2. For my setting, every 33ms, it will scan for a short time. Please check if it is caused by this reason. You can increase the scan rate to decrease the current consumption.

    Eason

  • Hi Eason,

    Thank you for reply.

    1. In our final application, we are going to use RTC wakeup every 10s. In that case,  do we still need to use Wake-Up interval? Do we need to take care of LTA explicitly or ROM library will take care of it when we wake up every time on RTC?

    2. I doubt its happening because of scan time. I kept set up running for long time. I see random current spikes as high as 120uA. I tried to see if there is any timing relationship, but there is no specific timing involved.

    With regards,

       Vishal

  • Hi Vishal,

    Why don't you use the timer supplied in CapTIvate Technology? Are you very care about average power consumption and the pick power consumption?

    My advice is that if you want your device react stable, you can't turn off the scanning for 10s.

    You don't need to take care of LTA. The lib will help you.

    Maybe you can use wake on Pro mode, it can save the power consumption. You can treat it as a button. If you press it, it will wake up to scan other buttons. Otherwise, there is no feedback if you touch other buttons directly. But EVM430-CAPMINI doesn't has one. You can use a button to simulate.

    Eason

  • Hi Eason,

    Yes.. I am running on AA batteries and power consumption is highly important. 10s is super long though. I will have to look into more details to optimize scanning period and power consumption.

    Thank you.

    With regards,

       Vishal

  • Hi Vishal,

    The first priority of CapTIvate is stability, which come out the customer experience. I really advice you to use all the choice supplied by our GUI which has been tested by TI.

    You can find the information you need in Ultra Low Power chapter of the UG 

    Hope it can help you. I will close this thread.

    Eason

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