STM32F105 DFU - how much current does it draw on PA9 pin?

Fleck · ‎2010-07-23

Posted on July 23, 2010 at 18:22

zoomcityzoom · ‎2011-08-08

Posted on August 09, 2011 at 00:01

The following measurements were made with a series resistor between USB_VBUS and PA9. The results imply that there is an equivalent of a 26.5K internal pull-down on PA9/OTG_FS_VBUS. Perhaps an internal voltage divider for comparator and detection of OTG_FS_VBUS?

USB_VBUS ---/\/\/\/\------ PA9

5V 6.4K 4V

USB_VBUS ---/\/\/\/\------ PA9

5V 2.644K 4.5V