STM32F4 vs STM32L4 on USB audio power consumption?

[andy2]

Posted on July 26, 2016 at 03:17

We are currently using the USB audio with the STM32F4, which works well. However, the power consumption of 40mA is something that we want to improve.  Would change to STM32L4 help the situation?  Our use is just using USB audio to I2S (SAI the same?) and virtual COM only.  

[Chris1]

Posted on July 28, 2016 at 00:18

Using an L4 device will definitely reduce current consumption.  The datasheets indicate typical consumption of about 30 mA for an F4 clocked at 60 MHz vs. about 9 mA for the L4 clocked at 64 MHz, for example (not including peripherals).

[Walid FTITI_O]

Posted on July 28, 2016 at 12:20

Hi Winix,

Abviously you will reduce your application's current consumption when using the Ultra-low power device as STM32L4. Take into account, that evzn with STM32F4 you can optimize your application's power consumption by applying some tips and tricks described in application note

http://www.st.com/content/ccc/resource/technical/document/application_note/13/0a/06/b9/1e/2f/4d/9d/DM00096220.pdf/files/DM00096220.pdf/jcr:content/translations/en.DM00096220.pdf

In case, you migrate from STM32F4 to STM32L4, you should give attention to some dependencies as system clock, pinout and peripherals... I recommend you to take a look to the Application note 

http://www.st.com/content/ccc/resource/technical/document/application_note/group0/87/fc/79/9d/3c/cc/49/84/DM00144612/files/DM00144612.pdf/jcr:content/translations/en.DM00144612.pdf

microcontrollers''. You can further open an STM32L4 USB example in STM32CubeL4 package to see how configuration is done there and make your document understanding happening quickly. -Hannibal-