I have a design running on nRF51 that I'm evaluating to run on nRF52. One important characteristic I'm looking for is to store it for long period with a minimum power consumption and a simple way to turn it back ON with a "user pusher" (not a reset button).
For that, on the nRF51, I use the system OFF without RAM retention and wakup from GPIO detect (connected with the puher). From the spec, I have 0.6 uA current consumption in this mode.
IOFF Current in SYSTEM OFF, no RAM retention. 0.6 μA
Same setup with nRF52 give 1.2 uA from spec, double of the nRF51 value :
IOFF_RAMOFF_RESET System OFF, No RAM retention, Wake on reset 0.3 μA
IOFF_RAMOFF_GPIO System OFF, No RAM retention, Wake on GPIO 1.2 μA
So my first question is why is there a so big difference (200%) between nRF51 and nRF52 ? And also a so big difference (400%) between wake on reset and wake on GPIO ?
I tried to think of an alternative way, to use the "pin reset" feature connected to this user button. But then, if I'm correct, I cannot change the assignment of the reset pin P.0.21 dynamically to disable reset and connect the "user pusher" as a normal GPIO input. Or maybe this is possible if I force a new reset on the CPU ?
Any idea on this ? Does someone else have similar question ?
