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Jonathan Forrest
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Powering external ICs off VBAT3V

Hi,

I am running the DA14580 in boost mode as I am running off a battery in the range 1.2-2V.
However, I am also using an external EEPROM to store the .hex file.

Currently I have a separate DC-DC boost converter to power the EEPROM which then has to be turned off after the DA14580 has booted.

Would it be possible to run the EEPROM directly off of VBAT3V. The 2.7V is sufficient for the EEPROM, but can it provide the 2mA or so that is required?

Note: After the DA14580 has booted it will turn power off to the EEPROM using a FET to keep total system current as low as possible.

JE_Dialog
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Hello Jonathan, will check

Hello Jonathan, will check for you : should not be a problem - teh spec is buried somewhere in the datasheet and i've just asked the HW team to point me towards it so that i can verify.

BR JE_Dialog

Jonathan Forrest
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Thanks JE_Dialog.

Thanks JE_Dialog.
I am guessing it wouldn't be a problem but I thought I should check. I can't find much at all about the VBAT3V output of the DC-DC converter in the datasheet. The info in Table 289 seems to refer to the VDCDC output.
In fact the only reason I know that the VBAT3V output defaults to 2.7V is from these forums (see: http://support.dialog-semiconductor.com/voltage-leakage-gpio-pins-eeprom...).
This fact (and the details of the register that can set the VBAT3V output voltage) appear to be absent from the datasheet.

TN_Dialog
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Jonathan,

Jonathan,

 

this is possible but you have got to make sure that the total power is keept very low. if you have EEPROM activity at the same time as RF activity you might see issues with the DCDC not being able to power the system.

 

Regards

TN_Dialog

JE_Dialog
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Hello Jonathan, we don't

Hello Jonathan, we don't specify /guarantee this value in boost mode, but we beleive couple of mA should be fine for EERPOM as long as you dont have RF activity (as pointed out by TN_Dialog).

Apologies i cannot be more specific.

BR JE_Dialog