Hi there,
I have two type nRF52 DK, pca10040 and pca10056. I know that pca10040's maximum txpower is 4dBm and pca10056's maximum txpower is 8dBm, and both boards have CR2032 coin battery socket.
I'd like to know that, can CR2032 can supply stable power source for both boards @maximum txpower? Theoretically.
Generally speaking, new lithium coin cell batteries can supply high peak currents without introducing a voltage drop, in some cases up to 100mA, even-tough its well above the rated drain current of ~200uA, see this thread on www.electronics.stackexchange.com. However, short burst drains with high peaks will affect the lifetime of the battery as described in the High pulse drain impact on CR2032 coin cell battery capacity whitepaper.
I did some measurements of the current consumption of the nRF52840 DK running the ble_app_hrs example, with TX output power set to +8dBm, DCDC enabled, and I am seeing peaks currents of 16mA
With the DCDC disabled I am seeing peak currents of 30mA
In short: Yes, you will be able to run the nRF52840 DK @ +8dBm from a CR2032 in both cases. The same applies for the nRF52832 DK @ +4dBm.
Bjørn
