Can the Discovery Board deliver 500mA for USB devices?

kroesswang_thomas · ‎2012-10-21

Posted on October 21, 2012 at 12:16

I'm currently developing a USB host and my device needs currents up to 500mA. Can the board deliver those

a) when powered by a PC over the debugger unit?

b) when powered externally by its pins?

raptorhal2 · ‎2012-10-23

Posted on October 24, 2012 at 04:49

You didn't say which USB you have on you PC. USB 2.0 is specified to 500 ma, and must power the Discovery board, so I presume the answer would be no to a). USB 3.0 is specified to 900 ma which should be enough. Check the board schematic for a diode between USB 5V and Board 5V that could cause a voltage drop.

You didn't say which Discovery Board. For the F4 Discovery, the STMPS2141STR USB switch on the Discovery board is rated to 500 ma, so I presume for the F4 the answer is yes to b). If you have a different board, check the USB switch part type and specs.

Cheers, Hal

kroesswang_thomas · ‎2012-10-24

Posted on October 24, 2012 at 21:38

Thanks for the info!

Just to be sure I'll buy a Y-USB-cable to supply the device externally.