TMS320F280039: Fab check for silk mask

Hello Chi,

Which PCN is the customer referring to? Can you describe the nature of the issue? e.g. What is the issue seen, how many devices affected, if this was an unchanged existing design/program or if there were modifications made?

I will need some time to check on the fab.

Best Regards,

Allison

Hi Allison, 

here attach the PCN change file as your reference.

 pcnAttachment-2023.pdf

the issue is Pin 16 and Pin 23 with larger current 0.3-0.4A; normal one is 0.1-0.2A, which will make customer system not stable. so here want to check if any effect in PCN change. thanks. 

BR

Chi

Hi Chi,

You can determine the fab by using the information given in the PCN and matching it to the symbol on top of chip per the snippet below:

All material meets the datasheet specifications. Can you please clarify what you mean by "current"? Is this leakage current? Leakage current should be on the order of uA. 

Best Regards,

Allison

Hi Allison,

It is not for leakage current, it is working current. 

BR

Chi

Hi Chi, 

Please see this app note: https://www.ti.com/lit/spract6

The MCU datasheet has values for parasitic capacitance for each analog pin. You can use this value to model the ADC input as shown in the app note. You can then calculate the current going to the ADC pin based on the ADC input voltage and the existing S+H capacitor voltage.

None of what is mentioned above was affected by the PCN.

Chi Zhang2 said:

the issue is Pin 16 and Pin 23 with larger current 0.3-0.4A; normal one is 0.1-0.2A

These are extremely high currents. This will not be possible with our ADCs. Do you mean mA? How are you measuring these currents?  

Best Regards,

Ben Collier