lowest battery level on DCDC mode

[sunnyjet16]

Hello,

I am using battery (3V) to supply nRF51822 system and the circuit is made according to DCDC mode circuit. My question is : what is lowest voltage the battery can go when nRF51822 system keeps working?

Thank you in advance.

Alex

[Ole Bauck]

Hi Alex,

The minimum supply voltage for the DC/DC is 2.1V, this is the point where it stops being effective (see graph on page 50 in Product Specification). You can switch to LDO when the voltage drops to this point. The LDO can operate down to 1.8V. You can do this by configuring power failure comparator on 2.1V. Then you will get a NRF_EVT_POWER_FAILURE_WARNING event from the SoftDevice and can turn off the DC/DC.

[sunnyjet16]

Thank you for your answer, Ole.