ble_app_uart consuming high power even at IDLE mode

RE: ble_app_uart consuming high power even at IDLE mode

Susheel Nuguru — Fri, 28 Aug 2020 12:34:29 GMT

Great samya, good to know that you solved it.

RE: ble_app_uart consuming high power even at IDLE mode

samyg — Fri, 28 Aug 2020 11:42:17 GMT

I managed to solve it. The problem isn't the code but it's how I power the DK. I shouldn't switch SW10 to ON, If I set to OFF, the voltage across the 10Ohm resistor when UART is enabled is about 700uA which is correct.

RE: ble_app_uart consuming high power even at IDLE mode

Susheel Nuguru — Fri, 28 Aug 2020 11:17:24 GMT

[quote user="samyg"]Also, if you uncomment uart_init() do you get an average current consumption of about 400uA?[/quote]

Yes, but the workaround makes the power go down.

Attaching my whole project folder as zip as you requested.

devzone.nordicsemi.com/.../ble_5F00_app_5F00_uart.zip

RE: ble_app_uart consuming high power even at IDLE mode

samyg — Fri, 28 Aug 2020 10:16:45 GMT

Yes I also disabled NRG_LOG_ENABLED in the sdk_config.h but I'm sitll getting 150mA when uart_init() is commented or 4mA when uart_init() is not commented. I've testing using both the oscilloscope and multimeter and both results are the same. Is it okay if I can have your code project where you copied my code and let me compared? I'm wondering if I accidentally enabled any other drivers/libraries that might cause additional current spikes.

Also, if you uncomment uart_init() do you get an average current consumption of about 400uA?

RE: ble_app_uart consuming high power even at IDLE mode

Susheel Nuguru — Fri, 28 Aug 2020 06:39:46 GMT

Hi Samya,

I used PCA100040 DK and I just disabled NRF_LOG_ENABLED in the sdk_config.h and commented out uart_init() in the file you provided and i get the current consumption like below

This confirms that the spike you are seeing is from the UART or maybe logs.

I even tried the code snipped you tried

    // Initialize.
    uart_init();
    app_uart_close();
    *(volatile uint32_t *)0x40002FFC = 0;
    *(volatile uint32_t *)0x40002FFC;
    *(volatile uint32_t *)0x40002FFC = 1;

and i get even lower

RE: ble_app_uart consuming high power even at IDLE mode

samyg — Thu, 27 Aug 2020 16:52:16 GMT

I tried the app_uart_close() as mentioned in the other thread but I still couldn't get the current consumption down. I called uart_init() then I close it before it starts advertising. I even tried commenting the whole thing out which means that uart is not initialised in the first place but current consumption is still about 150uA.

    uart_init();
    app_uart_close();
    *(volatile uint32_t *)0x40002FFC = 0;
    *(volatile uint32_t *)0x40002FFC;
    *(volatile uint32_t *)0x40002FFC = 1;

Did you manage to try out the code I shared on your DK and did you get the same current consumption?

RE: ble_app_uart consuming high power even at IDLE mode

samyg — Thu, 27 Aug 2020 08:09:57 GMT

The full version on the chip is NS2640 QIAAD0 1911AD. I will try the workaround later today.

RE: ble_app_uart consuming high power even at IDLE mode

Susheel Nuguru — Thu, 27 Aug 2020 07:49:47 GMT

Hi Samya,

It is possible that you are affected by the uart not releasing the hfclk. Can you please mention the lazer marking of the nRF chip to see the full version of the chip and the build code.

Can you please try the suggested workaround given by Jorgen in this thread.