I need to transfer almost all kinds of data (arrays, video/audio stream, control signals) between mcu and an Android smartphone. MCU will accumulate data from smartphone and further send it by other abstract communication channel. It will also bring data from this channel to smartphone. Host is located very close to device so the distance does not matter.

I thought it was obvious that wired bus better, but I started to doubt when found BLE chip DA14531 with the lowest current consumption of 1,5 mA in TX (20 dBm) and 2,3 mА in RX. Declared speed is 1 Mbps in this mode.

What I did not find was the current consumption of USB work in different data rates (e.g. Full Speed). In specification there is no parameters which describe exactly Tx/Rx current of the bus. There is only magnitude of max current that the host provides to device, but that's not what I need. Could you explain me which interface is worth using to achieve the lowest power consumption in this case, for example with the required data rate of 500-600 kbps?

  • \$\begingroup\$ "MCU" doesn't sound like it could forward the amount of data in a video stream. You will need to be way more specific what you deal with in terms of actual MCU hardware if you want us to estimate what uses how much power. \$\endgroup\$ – Marcus Müller Mar 24 at 13:44
  • \$\begingroup\$ Planned to use something with 32-bit ARM Cortex and USB embedded. For example STM32F042F6P6 or a bit more powerful GD32F105RGT6 with USB OTG. Is it ok if some video stream go through one of them? And by the way, can I communicate with smartphone's otg using non-otg mcu? \$\endgroup\$ – Hatsan125 Mar 24 at 14:01
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    \$\begingroup\$ That's going to be a hard: no, on the cortex-M0 you'll have a very hard time making that rate work (on which interface even?!), and I have no experience with your GD... but basically, you'll need draw a full block diagram that would involve all relevant components and their job to make a statement on power usage. \$\endgroup\$ – Marcus Müller Mar 24 at 14:22
  • \$\begingroup\$ Are you looking at minimizing the power consumption on the phone or on what you call the MCU? Which one should be the host? \$\endgroup\$ – pipe Mar 25 at 2:41
  • \$\begingroup\$ Yes, phone should be the host, of course. And power must be saved on both phone and MCU. I want them to consume less in total. If BLE provides overall minimisation better, then BLE should be used, otherwise - USB. \$\endgroup\$ – Hatsan125 Mar 26 at 7:56

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