Peak current when BLE-TX/RX and CPU run simultaneously

RE: Peak current when BLE-TX/RX and CPU run simultaneously

MartinBL — Tue, 28 Aug 2018 08:05:27 GMT

Hi,

You might look into Radio Notifications. It can be used to figure out when the radio is ramping up. I suppose you can use this to pause whatever tasks the CPU might be doing at the time.

Here is a relevant (but old) tutorial.

RE: Peak current when BLE-TX/RX and CPU run simultaneously

Saeed Ghasemi — Mon, 27 Aug 2018 11:34:11 GMT

Hi MartinBL!

Thank you for the detailed response.

I wonder there is known way of trying to halt the CPU at a specific time to avoid concurrent TX and CPU run, without delaying for too long. (like making a TX and sleeping the CPU for 10 ms. 10 ms being the connection interval.) ?

It could be nice to receive an interrupt 100us before a TX with a TX duration.

RE: Peak current when BLE-TX/RX and CPU run simultaneously

MartinBL — Mon, 27 Aug 2018 11:02:47 GMT

[quote user=""]Do these devices TX or RX while the CPU is running,[/quote]

Yes. You need to account for the possibility that the CPU is running while the radio is also active. But make sure you read up on the electrical specs and different ways of optimizing power. If you chose to utilize the internal DCDC regulator and TX at 0 dBm then you are looking at these values:

I_RX,1M,DCDC

RX only run current (DCDC, 3V) 1Msps / 1Msps BLE

5.4

I_TX,0dBM,DCDC

TX only run current (DCDC, 3V)P_RF = 0dBm

5.3

I_{DDFLASHCACHEDCDC}

CPU current, running from flash, cache enabled, DCDC 3V

3.7

Worst case is 9.1 mA with RX and CPU only concurrently.