• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 62 subscribers
  • Views 500 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS92682-Q1: TPS92682-Q1 Power dissipation CV-2phase Boost configuration

Harikrishnan Krishnan Nair
Prodigy 20 points
Part Number: TPS92682-Q1
Other Parts Discussed in Thread: TPS92682EVM-069, TPS92520EVM-133, TPS92520-Q1

Tool/software:

Hi All,

I am working on a LED array matrix project, in order to drive the LED array I have decided to use the combination of CV Boost and CC buck regulators. To satisfy this architecture I have chosen TPS92682-Q1 and TPS92520QDAPRQ1. My design consist of one boost converter and 5 buck with each of them have capability to deliver 2A(1A per ch) to the LEDs. 

I kindly request your assistance in resolving the following questions.

Operating voltage:- 9 to 16V

  1. How can I calculate the power dissipation ad thermal rise in the boost and each of the buck regulators.? Is there any calculation sheet available ?
  2. How to calculate the thermal rise in these chips, by considering a total 10A current has been drawn from the supply(each buck 2A)?
  3. Will the TPS92682 capable to support the total 10A current.

References used for this design are:-

  1. TPS92682EVM-069 CV 2-Phase Boost Controller Evaluation Module.
  2. TPS92520EVM-133 Dual 1.6-A Synchronous Buck LED Driver Evaluation Module

Thanks and regards,

Hari k

 

  • 0
    TI__Mastermind 23916 points

    Hello Hari,

    Can you give me more details about your design specifications.  I need to understand each buck output channel specification and I need more information about the boost converter specifications.  I also need clarification about what you wrote previously.  Specifically, you said the 682 support 10A, what do you mean by that?  Are you saying max input current, are you saying it has to support 10A on the output of the boost?  You also don't state the parameters for the boost converter such as output voltage and max output power.  Please specify the folllowing for the boost:

    Generally speaking we will not be able to support much more than 120-130W using the TPS92682-Q1 in a 2-phase boost.  

    I think it is important to specify all your buck output requirements.  You will also have to determine what is the max output power at one time, that will help determine what power level is needed for the boost converter.  Furthermore, we need to know the number of LEDs, the output current range, the Vf ot the LEDs used to determine min and max output voltage, and we will want to know if you guys will be doing shunt fet dimming or PWM dimming.  We will want to know PWM frequency and duty cycle range.  Each channel should be defined, and in your case that is 10 channels (5 dual channel bucks).  

    Here is an example of the kind of information that will help us determine how to help you best.  I broke out all the channels in the system and then define input and output parameters along with other important factors:  I doubt all the channels will be on at once, so you need to figure out the worst case output power.  Let me know what channels are on and what the input and output conditions are for that worst case max output power.  You said each channel is outputting 1A, but is that true and if so what is the output voltage range for each channel?

    I have some power calculation tools I can give you but I want to understand your system better.  

    -fhoude

  • +1 in reply to fhoude
    TI__Mastermind 23916 points

    The TPS92682-Q1 calculation tool is on the web.  

    https://www.ti.com/tool/download/SLUC690 

    Here is the TPS92520-Q1 Calculation tool and it is setup for a 682 + 2x520's.

      682-520x2 - ECU_Efficiency_Estimation_01242020.xlsx

    Please review the tools and let me know if you have questions.  

    -fhoude

  • 0 in reply to fhoude
    Prodigy 20 points

    Hello Fhoude,

    Thank you very much for sharing the calculation sheet and tool,  Actually we are planning to have a direct discussion with TI FAE regarding this matter. As we can't share much information over the public forum. Till the meeting is over we can keep this thread open later I may close this.

    thank you for your help.