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66AK2G12: Discrete power supply

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Replies: 16

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Part Number: 66AK2G12

Hi

My customer will design power supply using IC discrete for 66AK2G12.
Can I use the attached block diaglam?
Or are there the reference circuit designed IC discrete?

66AK2G12 Power supply.pdf

Best regards,
Yokota
  • Hi Yokota,

    This should be fine, as long as you comply with the Power-up sequence, Power-down sequence and the recommended operating conditions described in the datasheet.

    Best Regards,
    Yordan

     


     Please make sure you read the forum guidelines first.

  • In reply to Yordan Kovachev:

    Hi Yordan-san

    Thank you for the reply.
    As long as I read the datasheet of 66AK2G12, I must start up DVDD33 at first, but DVDD18, DVDD_DDR, CVDD and CVDD1 don't define power-up sequence.
    Is this understand correct?
    If this understanding is correct, can I start up them at same time?
    I will power down DVDD33 next DVDD18, DVDD_DDR, CVDD and CVDD1.

    Best regards,
    Yokota

  • In reply to takahiko yokota:

    Hi Yokota,

    If this understanding is correct, can I start up them at same time?


    The power-up sequence is given in Section 5.9.1.1Power-UpSequence, Figure 5-3. Power-Up Sequencing:
    DVDD33, DVDD33_USB start first. Then on Figure 5-3 you can see that DVDD18, AVDDA_DDRPLL, AVDDA_DSSPLL,AVDDA_MAINPLL, AVDDA_NSSPLL,AVDDA_UARTPLL, AVDDA_ICSSPLL,AVDDA_ARMPLL, DVDD_DDRDLL, and VDDAHV, DVDD_DDR, and CVDD, CVDD1 start at the same time.

    Power down sequence is the reverse order of the power up.

    Best Regards,
    Yordan

     


     Please make sure you read the forum guidelines first.

  • In reply to Yordan Kovachev:

    Hi Yordan-san

    Thank you for your quick response.
    Please let me confirm you just in case.
    Should I power up the loads except DVDD33, DVDD3_USB at same time?
    Or can I configure the sequence(3.3V⇒1.8V⇒1.35V⇒1V) in "TPS65911A User's Guide for 66AK2G12 Processor"?

    Best regards,
    Yokota
  • In reply to takahiko yokota:

    Hi,

    I apologize but I am kind of confused. The Power-up sequence is pretty straight forward:

    Assert POR.

    First you start DVDD33, DVDD3_USB.
    Then you start DVDD18, AVDDA_DDRPLL, AVDDA_DSSPLL,AVDDA_MAINPLL, AVDDA_NSSPLL,AVDDA_UARTPLL, AVDDA_ICSSPLL,AVDDA_ARMPLL, DVDD_DDRDLL, and VDDAHV, DVDD_DDR, and CVDD, CVDD1. 

    Exactly the same thing is depicted on the screenshot above.

    Best Regards,
    Yordan

     


     Please make sure you read the forum guidelines first.

  • In reply to Yordan Kovachev:

    Hi Yordan-san

    Thank you for the information.
    Can I start the loads except DVDDD33 and DVDD33_USB matter in both same time or in order?
    And should I power down contrary it?

    Best regards,
    Yokota
  • In reply to takahiko yokota:

    Yokota-san
    I have not completely gone through these posts, but in terms of an existing implementation have you already looked at K2G ICE board?
    http://www.ti.com/tool/K2GICE

    Regards
    Mukul
  • In reply to Mukul Bhatnagar:

    Hi Yordan-san

    Thank you for the information.
    I read the User's guide and schematic, I think that this EVM doesn't design about power-down sequence.
    If my understanding correct, should I desing power-down sequence contrary to power-up?

    Best regards,
    Yokota
  • In reply to takahiko yokota:

    Hi Yordan,

    Yokota-san is my colleague. Please let us confirm the power up sequence.

    You mentioned "Then you start DVDD18, AVDDA_DDRPLL, AVDDA_DSSPLL,AVDDA_MAINPLL, AVDDA_NSSPLL,AVDDA_UARTPLL, AVDDA_ICSSPLL,AVDDA_ARMPLL, DVDD_DDRDLL, and VDDAHV, DVDD_DDR, and CVDD, CVDD1."

    At this point, I believe there is no exact power up sequence requirement on these power lanes because of shaded in gray in the datasheet. Is that correct, right ? Take a look at the following red circle.

    Best Regards,
    NK

  • In reply to Naoki Kawada:

    Hi,

    Sorry for the confusion.

    My understanding is that they should start simultaneously, within the grey area shown in Figure 5-3 in the datasheet.  They can start at the beginning or at the end of the region you point in the red circles, but I believe the power-up sequence shows that CVDD, CVDD1, DVDD_DDR and DVDD18 (along with all other listed voltages in the DVDD18 rail) start simultaneously.

    Also, as Mukul noted, you can refer to the K2G ICE board

    Best Regards,
    Yordan

     


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