NRF51822 DCDC design

[zcmm]

NRF51822 supply voltage is 3V battery. When I design principle diagram, I have a question. Both AVDD and VCC_nRF are connect with the battery's positive?

[Øyvind Karlsen]

Hi,

When using DC/DC the AVDD pin should be connected to output of the DC/DC, i.e. AVDD to AVDD, and VCC_nRF to positive battery. This can be seen in the reference layout.

Best of luck, Øyvind

[zcmm]

thanks ,my device use DC-DC mode.i find the question. Useing DC-DC and LDO mode,Same board and tx power,LDO mode transmission distance is 90 meters,but DC-DC mode transmission distance is 45 meters.Can you tell me why?how solve it?