Voltage on VBAT3V pin when sleep in boost mode

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LiangZheng2k
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Voltage on VBAT3V pin when sleep in boost mode

Hi Dialog,
I'm using DA14580 in boost mode. It is powered by a 1.4V battery. The output voltage of VBAT3V pin is stable 2.7V when software runs in active mode. But, when software runs in extended sleep mode, the output voltage of VBAT3V pin is depends on the status of sleep or wakeup. 2.7V when wakeup. 1.4V when sleep. Does it mean boost DC-DC is shut down when sleep? I measured the voltage of any GPIO (output high) and found that the voltage was the same as VBAT3V. How to solve the problem of the different IO voltage between DA14580 and peripherals powered by an external independent boost DC-DC (2.7V) when in sleep?
Thanks.

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MT_dialog
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Hi LiangZheng2k,

Hi LiangZheng2k,

During sleep mode the DCDC is switched off. You dont have the option to keep the DCDC on while sleeping because it powers down with the core. I guess you can try to supply the other peripherals with somekind of external DCDC.

Thanks MT_dialog

LiangZheng2k
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Hi MT_dialog,

Hi MT_dialog,
Thank you for your reply.
This is a good idea to supply the other peripherals with external DCDC. In this way, I think the main problem is the different IO voltage level between DA14580 and other peripherals(some chips don't provide VDDIO pin) during sleep mode. During sleep mode , DA14580's GPIOs output high level of 1.4V. I'm afraid this is not safe to the peripherals which are powered by 2.7V. Designing a external DCDC to supply peripherals and DA14580 simultaneously, and keeping DA14580 to work in BUCK mode is a way to solve this problem, isn't it? Any suggestion?
Thanks again!

MT_dialog
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Hi LiangZheng2k,

Hi LiangZheng2k,

I am not aware what kind of peripherals you are using on your design. Yes, the different levels on the circuit will be a problem. If you have the option of using 3.3V in your design, then using the da in BUCK mode is perhaps the best solution. You can use the external DCDC to power the da and the peripherals that you have without any problems in IO voltage levels.

Thanks MT_dialog