current cosumption measurement

[nirmal@nordic]

Hi,

I am trying to measure and minimize current consumption ..... Following previous question on this forum,I found way to measure current on NRF51 DK by cutting SB9...and running power profile application for BLE

When I put mutimeter(FLUKE 289)in series on current measurement pins it to measure current, I found out that I can not see the beacon advertising in the NRF master control panel.

If I remove my multimeter(in series) and short the current measurement pins I can see beacon advertising the data in the master control panel...

I am running Power Profile application as it is.....using S130 and nrf SDK 11.0.0-2-alpha

1. Can anyone explain me the reason behind it ???

......... I set the tx_power for the radio to -12 dBm but it gets reseted to 0dBm..after service_init as NRF_RADIO->Tx_power register gets reseted to 0.

I tried to to find if any other function ,if using sd_ble_gap_tx_power_set() function , but did not see anywhere that it is being used.....

2. So, where exactly I should use this function to maintain upto what I set.....

[Stefan Birnir Sverrisson]

Hi

You should see in the nRF51-DK user guide how to measure current consumption. This is also stated in the nRF51 current consumption guide.

I do not know Fluke 289, but on my multimeter, which does not have auto-range capability, I need to select mA range when doing normal BLE transmission. Otherwise, if I choose uA range, then the multimeter will saturate, as the nRF51 needs a few milliamps of current during the instant of BLE transmission. So set the multimeter to mA setting when doing BLE transmission, and set the multimert to uA setting when measuring low current.

You can set the TX power with sd_ble_gap_tx_power_set after you initialize the softdevice and services.

[nirmal@nordic]

Thank you very much Stefen...Great to have input from you.... when I put ampmeter in mA range I could see the data on the Master control Panel...

So, what i understood as per you said is , when BLE is transmitting I will have to keep multimeter in mA range [for 30 seconds after I press the button1 or button2 in this case] , and then I can switch to uA range since it is at system_off_mode...

Am I right ???

[Stefan Birnir Sverrisson]

Correct !