SAMD20 decoupling capacitors

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Hello I have the following schematic:

Supply of the Bosch BMF055 (SAMD20 processor)

The Bosch BMF055 MEM actually contains an ATMEL SAMD20J18A cpu embeded in it.

The circuit is powered by a LiIon battery. Lately I am suffering from brownout issues when the circuit is shaken. Probably I guess that the poles of the battery might not be making perfect contact with the battery holder contacts of the circuit (I don't know).

Is it possible that if I add extra 'larger' caps (eg. 100 uF) before and after the voltage regulator, I might be able to solve that brownout dips (I guess they are really instantaneous)?

 

I have found the following link https://www.microchip.com/webdoc/samd20xplainedpro/ch05s02.html that says:

 

VDDCORE decoupling capacitor

The VDDCCORE output pin on SAMD20J18A has two decoupling capacitors, one 100nF and one 4.7μF. This might lead to a high power consumption when leaving STANDBY sleep mode and the regulator returns to normal operating mode.

Fix/Workaround:

  • Change the 4.7μF tantalum capacitor (C315) to 1μF ceramic capacitor.

 

Isn't that opposed to the brownout (meaning smaller caps have larger possibility of a brownout)?