nRF51 current consumption for common scenarios

The following is the estimated nRF51 current consumption during advertising with the DCDC disabled.

Advertising 1:
TX power: +4dBm
adv interval: 20ms (minimum advertising interval in normal adversising mode)
payload: 10 bytes
application processing: 2ms each adv interval.
Average current consumption: 1794 uA

Advertising 2:
TX power: +4dBm
adv interval: 1200ms
payload: 10 bytes
application processing: 2ms each adv interval.
Average current consumption: 33,4 uA

Advertising 3:
TX power: +4dBm
adv interval: 1200ms
payload: 10 bytes
application processing: 0ms each adv interval.
Average current consumption: 25,7 uA

Advertising 4:
TX power: -20dBm
adv interval: 1200ms
payload: 10 bytes
application processing: 0ms each adv interval.
Average current consumption: 19,6 uA

With nRF51 third revision hardware, DCDC reduces current consumption with up to 20% during advertising, see the nRF51822 PS 3.1 figure 11.


Central S120 single link connection (example 1):
Application processing 50 ms every 1 second: 235 uA

Transmitting and receiving packets 1 sec connection interval, RX 6 packets per interval, TX 6 packets per interval, 20 bytes per packet (includes base current +radio RX + radio TX + 16MHz crystal startup and run current + RTC + 32kHz crystal): 83 uA

Total: 318 uA

Central S120 single link connection (example 2):
Application processing 10 ms every 1 second: 67 uA

Transmitting and receiving packets 1 sec connection interval, RX 1 packet per interval, TX 1 packet per interval, 20 bytes per packet (includes base current +radio RX + radio TX + 16MHz crystal startup and run current + RTC + 32 kHz crystal): 22 uA

Total: 89 uA


S110 peripheral connection (example 1):

Connection interval: 1 second
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 0 bytes
Number of packets to send in each connection interval: 1 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 14.8uA

S110 peripheral connection (example 2):

Connection interval: 0.040 seconds
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 0 bytes
Number of packets to send in each connection interval: 1 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 255uA

S110 peripheral connection (example 3):

Connection interval: 1 second
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 20 bytes
Number of packets to send in each connection interval: 1 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 17.5uA

S110 peripheral connection (example 4):

Connection interval: 1 second
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 20 bytes
Number of packets to send in each connection interval: 4 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 42.2uA

S110 peripheral connection (example 5):

Connection interval: 0.040 seconds
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 20 bytes
Number of packets to send in each connection interval: 4 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 941uA


S110 peripheral connection (example 6):

Connection interval: 0.5 seconds
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 16 bytes
Number of packets to send in each connection interval: 1 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 29.4uA

S110 peripheral connection (example 7):

Connection interval: 4 seconds
Slave latency: 0
RX payload bytes in each packet: 0 bytes
TX payload bytes in each packet: 16 bytes
Number of packets to send in each connection interval: 1 packet
Number of packets to receive in each connection interval: 1 packet
Master clock 32kHz accuracy: 50ppm
Slave clock 32kHz accuracy: 20ppm
TX power: 0dBm
application processing: 0%
DCDC operation excluded

Current consumption nRF51: 7.8uA


  • DCDC operation is excluded in all connection examples. With nRF51 third revision hardware, DCDC reduces current consumption with up to 20% during radio activity, see the nRF51822 PS 3.1 figure 11.
  • If using internal 32kHz RC with temperature calibration instead instead of crystal: add ~2 uA.
  • If using internal 32kHz RC without temperature calibration instead instead of crystal: add ~10 uA.
Anonymous
  • image description Hi guys, I cannot see the exact time period of each state ,so how could I calculate the total power consumption ?

  • First I would like to say that this examples are really great. Second, is it possible to provide code examples of each scenario ? If will be great to have a better overview through source code.

  • @John These numbers were measured with a power analyzer on a single nRF51422 QFAC third revision chip. All RAM active. 3.3V supply voltage. Current consumption is however independent of supply voltage when using LDO mode, i.e. not DCDC mode or Low Voltage mode, see explanation on this thread.

    @sruthi I think these measurements were performed with S110 7.1.0 and S120 1.0.1. The DCDC mode was not recommended to use with nRF51 third revision until S110 8.0.0 / S120 2.0.0 / S130 1.0.0. So when using nRF51 third revision together with S110 8.0.0 or S120 2.0.0 or S130 1.0.0, the current consumpiton is slightly better than stated here, how much better depends on your application and supply voltage. The current consumption should be the same for S130 1.0.0 as for S110 8.0.0 when S130 is configured in peripheral mode. The current consumption should be the same for S130 1.0.0 as for S120 2.0.0 when S130 is configured in central mode.

  • Hi Nordic,

    Can you please add the current consumption for S130 application also ?

  • Was this data calculated or empirically gathered? If empirically gathered what was the hardware configuration? I.e. which processor, how much RAM active, battery voltages, etc.