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

Fleck
Associate II
Posted on July 23, 2010 at 18:22

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

1 REPLY 1
zoomcityzoom
Associate II
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