nRF52 Radio Performance and adaptive regulator control

[Dave_couling]

Why does the nRF52 only have +4dB output when most competitor chips are atleast +6dB (some up to +10dB). I understand that the RX has been improved by 3dB for a better overall link budget, but for beacon applications Tx rules. Is there any plan to release a higher power Tx version?

Looking over the new chip it seems the nRF52 has Adaptive Regulator Control. Does this mean it can smartly switch between internal LDO and external DCDC depending on current consumption?

Thanks,

DC

[Øyvind Karlsen]

Hi Dave,

For an energy efficient application, TX power is not key. A transmit power of 4dBm corresponds to 2.5mW, a transmit power of 10dBm corresponds to 10mW. While it's nice to have a lot of transmit power and a very high link budget you can't have it all in a low energy application. Usually the main requirement for your beacon is that it should last for a long time.

Note that to be compliant with BLE you need to have an EIRP(Effective Isotropic Radiated Power) of max 10mW. If you can achieve some of this through passive gain(e.g. antenna), that's great!

If you want to run proprietary you can still use a power amplifier, then you're just limited by the ISM-band power requirement.

There's a general trend in radio systems where you use lower TX power. High TX power was a workaround to achieve required range in the time before sensitive radios, think about old AM radio, e.g. radio Warsaw radio tower transmitting 2MW(63dB!).

Best regards,

Øyvind