LC filter on nRF51822

[mikelugarte]

Hi,

I am using a nRF51822 board and I wanted to know if the LC filter is necessary if I don't need to use any analog entrance or exit. I just need the BLE and a digital input.

[butch]

Which LC filter? AFAIK there is one on the antenna and one for the DCDC. The LC on say pin DEC2(?) is for the internal DCDC power supply (not sure I would call it a filter?) Whether you need that depends on your external voltage source greater than 2.1V (the min the DCDC requires) and whether you want the efficiency of the DCDC (vs LDO.)