STM32U599VIT6Q - Not able to flash through the JTAG pins

[anandtufast]

Hello,

I am using STM32U599VIT6Q for my project and I am unable to flash the MCU. When I turn on the board it consumes 50mA. Also, I am not using SMPS so I have connected the pins (VDDSMPS, VDDLXSPS, VDD11, and VSSSMPS) to the GND. Whenever I try to run the code it says cannot connect to the device. 

The boot0 pin is pulled low and I have NRST pulled high on board and I connected it to the oscilloscope and found that the pin goes low when Jlink tries to flash. 

Supply to the MCU is stable with 3.3V. 

Schematics is attached below for reference

Are SMPS pins a problem? Are they must use for this MCU?

Could you please help me with what could be a problem?

[AScha.3 · Accepted solution]

Hi,

1. why you buy a cpu with smps, when not using it ? (-Q version) You should use STM32U599VIT6 (no smps).

2. the core supply VDD11 - you short to gnd !   (no core - no fun !  You know ?  :)   )

If chip still alive - lucky !  

all this from rm ; read rm can be useful some time -->

So put 2 x 2u2 cer.caps on vdd11 pins - and you see: cpu still alive , or buy new. (Then this time w/o smps...)

And connect Vbat to VDD 3v3 , if you have no battery there. (nc is not allowed.)

[anandtufast]

Thank you

[AScha.3]

Hi,

NNOOOO !

VDD11 pin --- 2u2 ---- gnd .  (here the internal core voltage coming out - need cap to gnd . )

( 2x if 2 pins .)

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