abnormal reboot in nRF52832 (urgent)

[Roh]

Hi, guys.

Its developing with nRF52832.

I have a big problem rebooting. could you help me?

to solve this problem, I tried the following : (of course, it is very stable now.)

  > improving inrush current which of peripheral device to protect POR condition (like a 300mV, 300msec)

  > improving Batt. terminal's tension for conducted resistance reduction.

      - coin cell is LR44 and its internal resistance is 1.65 ohm.

      - working voltage 3V(=2 coincell)

The following are the pre-occurrence symptoms : 

  > continuous retry BLE connecting after occur communication disconnecting.

  > voltage drop (like below image)

ref. : Our SDK version is ver15.3 which is including a part of v16.0 and 17.2
        Because our device is a medical device, it is impossible to change the version.

[Roh]

thank you.

I will test it by reflecting your opinions.
I'll get back to you soon.

[Roh]

I'm back again with some good news.
I have done clear an abnormal rebooting issue.
I used two coin-cell as series. the problem was contact resistance between two cell.
the cell got 'Ni' plating. especially the face of cathode was unstable plating and also had a mash structure.
if a bad plating cell met with a minimum thickness cell unit, the power stability was broken and than occurred abnormal rebooting.

i had to put a gold tape between two cell for improving unstable contact resistance.