• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 378 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: Common Supply Configuration

Jejomar Ildefonso
Genius 9490 points
Part Number: TPS92682-Q1

Hi Team,

Do we have a TPS92682-Q1 sample application circuit showing a configuration for common supply voltage on the two channels? The device fully covers our customer's requirements but they are restricted to use a common supply voltage configuration - which is quite challenging with TPS92682-Q1 as it operates common ground.

As a substitute, do we have alternate solution/LED driver to offer which uses N-channel MOSFET instead?

Thanks in advance!


Kind Regards,

Jejomar

  • 0
    TI__Mastermind 18890 points

    Hi Jejomar,

    I have a hard time understanding you question here.  They can use one supply and provide two separated regulated outputs from this one input if that's what you are asking?  If that is not the case then please give me a block diagram or schematic of how they want to use it and I will comment on that.

    Thanks Tuan

  • 0 in reply to Tuan Tran74
    TI__Genius 9490 points

    Hi Tuan,

    Many thanks for looking into this. Here is a simple block diagram of what they would like to achieve (Resistors are the LEDs): 


    Perhaps it would also be interesting to know that the LED stripes (warm white and cold white) have one line for + and two lines for -. Which is why there is a common supply voltage.


    Kind Regards,

    Jejomar

  • 0 in reply to Jejomar Ildefonso
    TI__Mastermind 18890 points

    Hi Jejomar,

    Let me see if this is what you mean...So you have 2 LED's in a package but the Anodes (+) are tied together and the Cathodes (-) are two different connection is that correct?

    What you have in the block diagram looks like a linear driver which would make sense here given my assumption above.  The TPS92682 is a switching controller and so would not be applicable here as a linear driver as shown in your block diagram.

    You will need to reach out to the Linear LED (PSIL-LED) group for a part that is applicable here for you.

    Thanks Tuan

  • 0 in reply to Tuan Tran74
    Prodigy 10 points

    Hi Tuan, 

    thanks for the answer. I guess my block diagram was a bit misleading, I'm sorry.

    You are right with the assumption that the Anodes are tied together. But our "package" includes two LED strings with several LEDs, which need 1.5A per string with Vin=48V.Correct me, if I'm wrong, but in my understanding this is a bit much for a linear driver. So I searched for a switched constant current driver and ended up with your TPS92682.

    With this new information, do you still think a linear driver is practicable? 

    Best regards

     David

  • 0 in reply to David Urig
    TI__Mastermind 18890 points

    Hi David,

    What is the LED string voltage?  Are the LED package with the same LED's with same number of LED on each string?  Are you trying to drive different current thru each LED string?  If you are trying to drive the same current thru the each string then you can drive them in parallel,  The current will be well match if the LED's are well matched.  You will have to verify that for yourself. 

    If you are driving different current or the LED's are not well match and you want to use a switching controller then you will need to configure two regulators and configure it as a floating Buck.  This will let you use the common Anode t be tied to the input voltage.

    Thanks Tuan