Hello I have what I hope is a simple question regarding the Internal DC/DC on the nRF52832 and thus nRF52810. I am assuming it is the same internal design, correct between these 2 devices...
Use Case: -12dBm Tx Power, Beacon interval 2seconds, VBat/Vdd = 1.8-3.1V, Internal DC/DC Enabled, External DC/DC Boost is Enabled only upon Beacon Connecting to Client Vdd Boost = 3.3V.
What is the minimum Vdd that the internal DC/DC can operate from. The nRF52832 indicates that it can operate from 1.7-3.6V but I don't see any specific mention as to what the minimum voltage that the DC/DC requires to still function correctly?
My question stems from a scenario that I am observing in which we are powered from 2 AAA batteries and using an external DC/DC Boost in Bypass Mode 98% of the time(just passes battery voltage when the external DC/DC boost is disabled). What I am seeing is that at VBat < ~2.0 the IDD rises significantly in which I would expect the IDD to continue to drop if the Core voltage the internal DC/DC is regulating to is 1.3V as is shown on the Diagrams such as Figure 14: in the nRF52832 datasheet.
Measurements taken are shown below. The Minimum IDD(in between Tx) stays relatively steady at ~12-14uA.
VDD = 2.4V Peak IDD = 210uA
VDD = 2.3V Peak IDD = 214uA
VDD = 2.2V Peak IDD = 219uA
VDD = 2.1V Peak IDD = 226uA
VDD = 2.0V Peak IDD = 231uA
VDD = 1.9V Peak IDD = 242uA
VDD = 1.8V Peak IDD = 255uA
Based on this is there a crossover where the DC/DC should be disabled because of inefficiencies at lower voltages?
Secondarily is it safe to Enable/Disable the internal DC/DC on the fly?
Regards,
Sensor Maestros
