Fault Tolerant I/O

adrian3 · ‎2007-08-19

Posted on August 20, 2007 at 05:54

Fault Tolerant I/O

adrian3 · ‎2011-05-17

Posted on May 17, 2011 at 12:15

In the pin descriptions section of the data sheet (Table 3), each pin is defined as whether it is 5V tolerant (FT). Unfortunately, PB5 (which I hope to use as an open drain output - returned to 5V) is not shown as being FT.

Q. Does the term 'FT' refer to the input or the output function - or both?

Q. What would be the best way to ensure this pin is FT?

I was thinking along the lines of an N channel FET as per Figure 20 in the UM0426 Evaluation board User Manual

Any thoughts?

[ This message was edited by: _adrian_ on 25-07-2007 11:47 ]

anis2399 · ‎2011-05-17

Posted on May 17, 2011 at 12:15

Hi _adrian_,

- The 5V tolerant (FT) refers to the input level for the pins... the STM32 pins with FT capability can support 5V as input but can't generate 5V.

- The best way to use the PB5 as FT is to add an external level translator...

Regards

The Lionheart