Hi,
We are going to evaluate: nRF52840 with a large NOR flash.
This Flash has two options: 3.0V / 50 mA max, Or 1.8V / 50 mA max.
We prefere to use the 1.8V type, as this is better low power.
But the nRF52840 datasheets specifies: max external current at VDD = 25 mA.
We gone use a 3.6V Li-ion battery, direct to VddH. Reg0 = DCDC mode. VDD = delaut = 1.8V.
The flash seems not to be power bij VDD as the DCDC seems not to deliver enough current.
The VDD shall supply the complete nRF chip: Core, peripherals, BLE.
BLE will also require less battery energy if we set VDD to 1.8V. BLE needs 16 mA
The Core activity is not known yet, but lets state 50%. That will be 2 mA?
Then peripherals and IO. Not known yet.
Our question is about the DCDC it's self. How much current can it deliver?
Than we can calculate the remainig current for the flash.
