nRF52840 Power consumption with SLEEP OFF mode and SLEEP ON mode

[BilalAliAhmad]

We are nRF52840 in one of our products. When we use SYSTEM OFF mode with with hardware design, current consumption is around 3uA but when we use SYSTEM ON mode with RAM retention current increases to 17uA. But according to datasheet of nRF52840, current consumption is 2.35uA when SYSTEM ON mode is used with RAM retention. But considering our current in SYSTEM off mode is 3uA, it should be around 5uA in SYSTEM ON mode. 

We are using zephyr PM APIs to take device into SYSTEM OFF or SYSTEM ON mode like this:
pm_power_state_force((struct pm_state_info){PM_STATE_SOFT_OFF, 0, 0});\

we tried both these are for SYSTEM ON mode: PM_STATE_STANDBY and PM_STATE_SUSPEND_TO_RAM but current is still 17uA.

Can you please guide use where we are doing wrong or is this a correct way to use it? 

[Simonr]

Hi

Please specify what you mean here, because RAM retention is used by default in System ON mode, so do you mean system OFF here is drawing 17uA? If so, I assume there is some leakage current somewhere in your circuit. Do you also see this current consumption when measuring current consumption on a DK? And how exactly are you measuring current consumption here?

Best regards,

Simon

[BilalAliAhmad]

Current consumption is 17uA with system ON mode and 3.5uA with System OFF mode. If there is a leakage current in the circuit why it drops to 3.5uA in system off mode? We are using power profiler kit to measure current consumption.