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4.4 Current Consumption

Power mode

hardware.xml

Min

Typ

Max

Unit

Transmit

(3V0 supply,

without DCDC)

<txpower power = ”1”/>

<slow clock enable = ”true”/>

25

mA

<txpower power = ”9”/>

<slow clock enable = ”true”/>

36

mA

<txpower power = ”9”/>

<slow

clock enable = ”false”/>

39

mA

Transmit

(With DCDC)

<txpower power = ”9”/>

<slow clock enable = ”true”/>

32 **

mA

<txpower power = ”9”/>

<slow clock enable = ”false”/>

35 **

mA

Receive

<slow clock enable = ”true”/>

28

mA

<slow clock enable

= ”false”/>

33

mA

Power mode 1

<sleeposc enable="true" ppm="30" />

2.7

mA

Power mode 2

<sleeposc enable="true" ppm="30" />

1.3

µA

Power mode 3

***

0.5

µA

**) Using DCDC reduces transmit power by ~2 dB and thus lowers also the peak current drawn by the module

***) To enter PM1 and PM2 sleep oscillator must be enabled in the hardware.xml. PM3 is not dependent on

the sleep clock. The module will enter PM3 automatically when there is no activity which would require clock.

PM3 can be disabled in hard

ware.xml, for example <sleep enable=“true” max_mode=”2” />

Figure 2: BLE121LR TX peak current as a function of the setting in the HW configuration file

1ms/div

TX peak 39 mA

(slow clock disabled)

RX peak 33 mA

(slow clock disabled)

TX peak 36 mA

(slow clock enabled)

RX peak 28 mA

(slow clock enabled)

11mA

11mA

1.3uA

1.3uA

Figure 3: Typical current consumption profile while advertising