I am not quite certain what the advantages/disadvantages are of using LDV vs DCDC if you are using an external regulator. In my case i use a LiPo battery outputting ~4.2V so i need to drop the voltage down to something 1.8-3.6V for the nRF51822.
Would it be more power efficient to use the LDO @ 1.8V or DCDC at some higher voltage like 2.0V? Either is an option im just not sure since i hear DCDC is more power efficient than LDO.
The DCDC is safe to use with the third revision nRF51 hardware and softdevices S110 8.0.0, S120 2.0.0, S130 1.0.0, S210 5.0.0 or S310 3.0.0. See the nRF51 compatibility matrix to identify third revision…
To answer your question, more information is needed. You need to calculate the average current consumption of your application which includes CPU, peripherals, and the radio, and also the amount of time the chip is in various low power modes. If you are switching in and out of low power modes, you need to also estimate how often, and the duration of the ON times. This is because there is a startup time with respect to the DCDC converter.
Are there specific things in section 188.8.131.52 that need clarification?