STM32 Jtag

[luisf]

Posted on February 10, 2011 at 12:08

STM32 Jtag

[Tesla DeLorean]

Posted on May 17, 2011 at 14:24

Should i use or not external Pull-Ups?

On-chip pull-ups/downs are usually rather weak (around 100K for most I'm familiar with). I would provide external ones, or at least the pads to place them if I wanted them later.

[js23]

Posted on May 17, 2011 at 14:24

The Reference Manual says the following in 30.4.3:

''Having embedded pull-ups and pull-downs removes the need to add external resistors.''

The internal resistors are typ 40k (min. 30k, max 50k), so this is true under ''normal'' operating conditions. However, if your app is running in extremly noisy environments, you might consider adding external resistors. Switching the JTAG pins to normal I/O mode after reset can be a solution, too. I personally never used external resistors. Until now without any problem.

[Nickname12657_O]

Posted on May 17, 2011 at 14:24

Dear all,

I confirm that, no need to use external pull-ups/down, we already have them in our STM32 series and are widely used by most of our customers at production without claims since 2007. Cheers, STOne-32.