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TMS320F280049C-Q1: F280049CPZQR

Asha C
Intellectual 475 points

Part Number: TMS320F280049C-Q1

Hello ,

Could you please provide feedback for the below queries:

1. If the orderable part number or MPN F280049CPZQR is a automotive qualified part.

If not please let know the orderable part number.

2. Is monitoring VDDIO suggested since it has internal Monitoring?

 In our use case we are using Internal LDO/DC DC for VDD. So in this case do you suggest monitoring the power rails?

3. Regarding crystal , I see a suggestion of 6 to 12pF load capacitance in datasheet but in the EVM it uses 18pF part , can we go ahead with the same?

https://www.ti.com/lit/zip/sprr421 - This is the EVM referred.

4. Do you have a tool which calculates the overall power dissipation / calculation based on the peripherals which are used?

I see only one current info given with specified use case. We are using GPIOs from uC which needs to drive external signals , so how to calculate the power dissipation in this case.

Thank you in advance!

  • 0
    TI__Mastermind 36526 points

    Hi,

    Asha C said:
    1. If the orderable part number or MPN F280049CPZQR is a automotive qualified part.

    Yes it is.

    Asha C said:
    2. Is monitoring VDDIO suggested since it has internal Monitoring?

    This really depends on the application and whether VDDIO is expected to be unstable.

    Asha C said:
    3. Regarding crystal , I see a suggestion of 6 to 12pF load capacitance in datasheet but in the EVM it uses 18pF part , can we go ahead with the same?

    The Y2 crystal's datasheet lists a minimum load capacitance of 8pF, and there is a load capacitance of 7.5pF + PCB parasitic capacitance which is likely close to 10pF total. 

    Depending on your PCB layout, this should be fine, but you could increase C38 and C39 slightly if you want to be careful. 

    Asha C said:
    4. Do you have a tool which calculates the overall power dissipation / calculation based on the peripherals which are used?

    We do not have such a tool, just estimates in the datasheet.

    Best Regards,

    Ben Collier

  • 0
    Intellectual 475 points

    Hello Ben Collier,

    Thanks for the response.

    Regarding Question 3 , i still have open point:

    Asha ---> Regarding crystal , I see a suggestion of 6 to 12pF load capacitance in datasheet but in the EVM it uses 18pF part , can we go ahead with the same?

    Ben -----> The Y2 crystal's datasheet lists a minimum load capacitance of 8pF, and there is a load capacitance of 7.5pF + PCB parasitic capacitance which is likely close to 10pF total. 

    Depending on your PCB layout, this should be fine, but you could increase C38 and C39 slightly if you want to be careful. 

    Asha -----> As per the datasheet minimum load capacitance is the ones which is available in that series , as per the part used in the design it is a 18pF part which is 'ECS-200-18-30B-AGN-TR.

  • 0 in reply to Asha C
    TI__Mastermind 36526 points

    Hi,

    Unless I'm looking at the wrong datasheet, I see this: 

    Best Regards,

    Ben Collier

  • 0 in reply to Benjamin Collier
    Intellectual 475 points

    Yes , datasheet is the right ones but load capacitance is mapped as per MPN as they mention Specify in P/N on conditions.

    ECS-200-18-30B-AGN-TR

  • 0 in reply to Asha C
    TI__Guru* 95315 points

    Asha,

              In future, when you have multiple (unrelated) questions, please open a separate thread for each question with an appropriate title. This would allow us to route each query to the most appropriate expert. It would also make tracking easy for both of us, besides making future searches easy.

  • 0 in reply to Asha C
    TI__Mastermind 36526 points

    Asha,

    I would also like to apologize for my previous answer, we do have a tool that calculates the overall power dissipation for this device: 

    https://www.ti.com/tool/C2000-F28004X-POWER-EST-CALC

    Best Regards,

    Ben Collier

  • 0 in reply to Benjamin Collier
    Intellectual 475 points

    Hello Benjamin,

    Is there any response for the previous question asked wrt crsytal load capacitance selected. It is 18pF which is deviating from datasheet spec.

    Yes , datasheet is the right ones but load capacitance is mapped as per MPN as they mention Specify in P/N on conditions.

    ECS-200-18-30B-AGN-TR

  • 0 in reply to Asha C
    TI__Guru* 95315 points

    Asha,

              Datasheet is specifying a MIN of 12pF and MAX of 24pF. So, a crystal with 18pF load capacitance is OK.

  • 0 in reply to Hareesh Janakiraman
    Intellectual 475 points

    Hareesh,

    As per 7.9.3.4.7 Crystal Oscillator Specifications in datasheet , CL1 and CL2 is mentioned as 12pF to 24pF which corresponds to the capacitors

    where as under 7.9.3.4.4 How to Choose a Crystal , as per point 3: Check that the load capacitance requirement of the crystal manufacturer is within 6 pF and 12 pF per specifications for 20 MHz.

    Could you please provide your feedback on the same!

  • 0 in reply to Asha C
    TI__Guru* 95315 points

    CL1 and CL2 refer to the capacitors. Since they are in series, effective load capacitance is CL/2. That is how the 12 & 24 spec becomes 6 & 12 respectively.

  • 0 in reply to Hareesh Janakiraman
    Intellectual 475 points

    Hello , 

    WRT CL1 , CL2 if I am right is not crystal load capacitance right. Suggestion is 12 to 24pF.(parallel capacitors to crystal).

    What is the suggested crystal load capacitance? Isnt it 6pF to 12pF.as per point 3 below ,  but we have 18pF crystal in EVM . This is my query

    As per the below statement , 

    7.9.3.4.4 How to Choose a Crystal

    1. Pick a crystal frequency (for example, 20 MHz).

    2. Check that the ESR of the crystal <=50 Ω per specifications for 20 MHz

    . 3. Check that the load capacitance requirement of the crystal manufacturer is within 6 pF and 12 pF per specifications for 20 MHz.

    • As mentioned, CL1 and CL2 are in series; so, provided CL1 = CL2, effective load capacitance CL = [CL1]/2. • Adding board parasitics to this results in CL = [CL1]/2 + Cstray

  • 0 in reply to Asha C
    TI__Guru* 95315 points
    Asha C said:
    WRT CL1 , CL2 if I am right is not crystal load capacitance right.

    As already clarified in my previous post, CL1 and CL2 refer to the capacitors.

    Asha C said:
    What is the suggested crystal load capacitance? Isnt it 6pF to 12pF.as per point 3 below ,

    Yes, that is the capacitance seen by the crystal.

    Asha C said:
    but we have 18pF crystal in EVM .

    There is no "EVM" for this product. We only have the Lauchpad and ControlCard. Having said that, I understand your concern. You are highlighting the 18pF load capacitance on these boards which is more than what the datasheet recommends. This will impact the accuracy but only in the PPM range. Cost and component availability may occasionally play a role in component selection for evaluation platforms. However, for your end-product, please abide by the datasheet guidelines. Parameters such as reliable start-up, operation over the entire temperature range/component aging typically supersedes compromise of accuracy by a few PPM.