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.

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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

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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

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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

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• 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.