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Schematic on new STM32F103ZET6 development board

tkjmail2
Associate II
Posted on March 11, 2010 at 22:56

Schematic on new STM32F103ZET6 development board

2 REPLIES 2
bfredr
Associate
Posted on May 17, 2011 at 13:43

Hej Thomas,

Few smaller things:

The JTCK line has a weak internal pull down, so consider changing your external pull up to a pull down if you are concerned about your current consumption in stop mode.

I've also seen it recommended to have 100n bypass on the reset line. This signal is quite ''hot'' so it can be triggered with a multimeter.

Be careful with the 32 kHz xtals load capacitance. 12p will not work reliably. Use a 6p xtal. With short lines and few pF in your layout your capacitors are down at 6-7pF but 10p might also work fine.

If you add a testpoint on the tamper pin, you can later check the frequency accuracy and adjust it if necessary.

You are not using the VREFs ?

I would connect them to 33 and 30 and maybe add a small resistor in series with L1 to filter the noise.

Good Luck, and let us know how it worked.

Bo

tkjmail2
Associate II
Posted on May 17, 2011 at 13:43

Hi Bo.

Thank you for your reply.

The missing VREF connections was a mistake - but the others has been changed now.

Please take a look at it now, and tell me if the changes is correct?

http://www.tkjweb.dk/STM32F103ZET6_Board_Rev2.png

Best Regards

Thomas Jespersen