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Freescale MK10DN512ZVLL10 ADC module/Peripheral conversions slowing down after 30-90 days and subsequently stalling/damaged permanently.

Question asked by Brijesh Lavu on Dec 14, 2015
Latest reply on Dec 17, 2015 by Brijesh Lavu

Chip: Freescale MK10DN512ZVLL10-4N30D (Kinetis K10)

Issue: ADC module/Peripheral conversions slowing down after 30-90 days and subsequently stalling/damaged permanently.

 

No of chips affected/damaged:  20 Nos.

Core Clock: 100Mhz

Bus Clock:   50MHz

ADC Operating Frequency: 50/8=6.25MHz

Hardware Average: No/Disabled

Long Sample: Yes

Long Sample clocks: Extra cycles

Total ADCs connected: 11

No. of Differential channels connected: 4

ADC Resolution :16-bit

No. of Single-ended channels connected: 7

ADC Resolution :16-bit  

 

In-depth Problem:

 

  • The chip ADC module works as designed/engineered/coded in our production line & factory testing.
  • Once the chip is working in real-world application(industrial data aquisition), its works fine for atleast 30 days.
  • The trouble starts anywhere between 30-90 days where the ADC conversions really slows down & ultimately freezes.
  • Henceforth the aforementioned Chip-ADC module absolutely doesnt work on any valid ADC input signal.
  • Once the ADC clock is lowered or increased in code & reflashed, the ADC module reworks but just for a day or two.
  • Basically dead for future ADC conversions.
  • The code also uses FTM that is derived from Bus clock.It works absolutely perfect.
  • Rest all of the chip modules work as expected.
  • No heating or physical damage observed or loose solder contacts.
  • The VREF & VVA are shorted=3.3V same as the supply of the chip.
  • The VREFH & VREFL voltages are steady & corresponding pins in place.
  • No. of chips failed in this fashion ~20 Nos at different geolocations.

 

 

Attached is the Code* for Core clock, ADC clock & ADC reading.

Also attached is the schematic* for reference.

 

*Only ADC section.other details/specifics taken out

 

Please acknowledge, analyze, diagnose & suggest what is going wrong/what is causing ADC to damage/any corrections in code or schematic.Any suggestions will be appreciated.

 

Brij

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