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Pin termination normally & after power up STM32

Question asked by takniki.vindhyachal on Aug 14, 2015
Latest reply on Aug 15, 2015 by takniki.vindhyachal
I am using STM32F205 LQFP64 & want to know if below configuration of pin are ok. I use SWD method.I have grouped pins as:


1. vbat:  If not used, connect it to Vdd & decouple by 0.1uf cap.


2. PA0-PA15: If any of pin is not used, make it internal pull up or output low after power up 
Except PA13(SWDAT) & PA14(SWCLK).Leave these pins float as they have internal pull-up/down according to datasheet.


3. PB0-PB15: If any of pin is not used, make it internal pull up or output low after power up


4. PC0-PC15: If any of pin is not used, make it internal pull up or output low after power up. 
Except PC13, PC14, PC15 as these have alternate function with RTC oscillator & alarm. Should I also make them internal pull up or output low after power up in case not used?


5. PD2: if not used, make it internal pull up or output low after power up


6. PH0-PH1: Alternate function with main oscillator. Should I also make them internal pull up or output low after power up in case I am using internal oscillator?


7. NRST: decouple with 0.1uf cap, it has internal pull-up according to datasheet.


8. Vcap1-vcap2: Decouple with 2.2uF cap each.


9. VDD1-VDD4, VSS3-VSS4: Decouple each vdd with 0.1uF cap, with additional 4.7uF decouple cap on one vdd.


10. VDDA, VSSA: decouple with 0.1uf & 1uf cap.


11. Boot: pull down with 10K because code is exceuted form flash.

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