Part Number: CC3220
Hi everyone!
i have a very big problem - my pcb design burn six chips.
how it was (chronology):
1) at June i make a 1st version of pcb design and it didn't start. I soldered more thiker wires from L2 (datasheet marks) to pins 25, 36 and from L4 to pins 9 and 56. and i used 10uH for all L. And first ver ocb design start working.
2) at August I draw a new design. version two. two weeks ago I soldered a first plate with a new design.
no start! 3.3V, 1.9V, 1.2V was ok. Uniflash had ok connection, and ok firmware loading. But firmware no started!
3)ok. I soldered out cc3220sf chip from my pcb and solder it to luanchpad. everething same.
4) (my mistake) i took cc3220sf and flash memory from first ver of plate and solder it to 2 ver.
(clarification: my program work like this: power on -> check cause(gpio/timer) of wake up -> check GPIO -> connect to AP/WPS (if first start) -> send to server GPIO state -> go to hib for 180 secs). if everything ok - every 3 min i read by uart debug log of every step.
But! It becames rebooting every 2-3 second! at normal work i have 15-20 strings of debug log, but in this case i had 10 strings of log maximum and reboot. few moments later - 5 strings, and later - 1 string. and no start firmwware st finish. and chips was real HOT (100-110 Celsius degrees).
i burned first two chips like this
1st chip - pins 46 and 39 are connected with GND pad
2nd chip - pins 41 and 39 are connected with GND pad
5) i thought the problem is with wrong GPIO config. i check code - no problems.
i tried just blink the led - same problems. and two more burned chips.
3rd chip - pin 45 is connected with GND pad
4th chip - pin 46 is connected with GND pad
6) i solder more thicker wire to pins 10 54 44 39 37. and 5th and 6th chip are burned out.
5th chip - all pins have no connection with gnd but chip no start
6th chip - pin 45 is connected with GND pad
how i checked chips - solder launchpad many times (*** method but 100% help)
what i have now - firmware is ok. cfg GPIO is ok. problem somewhere in pcb design
i attach schematic and pcb file. i work at pcad2004 but you can import files at altium.
pls help!
