• State
  • Locked Locked
  • Replies 4 replies
  • Subscribers 33 subscribers
  • Views 486 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TPS25740B: TPS25740B Work Problem

user4731692
Prodigy 50 points
Part Number: TPS25740B

Hello，

I used the TPS25740b as a PD protocol communication. The design of the chip is based on the solution provided at www.ti.com.cn/.../TIDA-01622. The test module uses a 5V input power supply. After the scammer is connected, it expects to output 5V, run at no load, and then test the signal on the CC line. The signal waveform is as shown in the figure, where yellow is CC1 and blue is CC2. Looking at the waveform seems to trigger the protection, but I can't find the reason and hope to get help.

  • 0
    TI__Mastermind 36751 points

    Hello,

    We are looking at your request and processing the information. We should have a response to you early next week.

    In the meantime, do you have a TPS25740BEVM that can reproduce the issue?

    Thank you,
    Eric

  • 0
    TI__Genius 9630 points

    Hello,

    Where is the 5 V being applied to? The adapter as a whole supports between 85 VAC ~285 VAC, so 5V would be too low to be converted if you are applying that to the input of the AC/DC adapter. 

    Also, what kind of scanner are you using? Is it a PD analyzer?

    Thank you,

    Emma

  • 0 in reply to Emma Hoying
    Prodigy 50 points

    Hello Emma,

    Thank you for your reply. I am sorry that I did not describe clearly.

    In order to test whether the PD protocol chip can work normally, I connect the PD module to the AC/DC part of the upper level, and then use the 5V independent power supply as the input of the PD module instead of using 5V as the input of the AC / DC module. Connected to the output is a device that triggers the PD protocol, which can handshake with the TPS25740B and output 5V.

    As shown in the figure, the Vo port is connected to 5V, and the output is connected to the spoof through the type-c interface.

    Maybe you think of scammer (the device that triggers the PD protocol and completes the handshake communication with the TPS25740B) as a scanner. I did not use the scanner.

    Thank you,

    learner

  • 0 in reply to user4731692
    TI__Genius 9630 points

    Hello,

    The 5V you've connected to the Vo could be back feeding the converter and triggering the overvoltage protection. Try to test the TPS25740B on its own with the TPS25740B EVM and see if you get the same issue.

    Thank you,

    Emma