• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 16 subscribers
  • Views 217 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.

TS3A227E: Using the 'DET Trigger' bit

Derren Crome
Prodigy 20 points
Part Number: TS3A227E

Hi, 

I'm using the TS3A227E on a prototype board I have designed.  I am trying to use only the DET Trigger bit to perform a detection (without needing to toggle the DET TRIGGER pin) .

When using the external DET_TRIIGGER pin (pulled low) it successfully detects the connected headphones, however using the 'DET Trigger' bit within the Device Settings register, it doesn't.  Apparently the 'DET Trigger' bit should clear on completion, on my board it remains high indefinitely (unless I pull-low the DET_TRIGGER pin).  Keeping DET TRIGGER pin permanently low doesn't work.

Any ideas?

Thanks

  • 0
    TI__Expert 5660 points

    Hi Derren,

    Thanks for your question.

    To start, could you send the exact sequence and timing table of your manual control method, as well as register map dump after every change?

    Keep in mind that type detection does not run in the following cases:

    Thank you!

    Kate

  • 0 in reply to Kate Dickson
    Prodigy 20 points

    Kate,

    Thanks for the prompt response.

    Is it possible to have the DET_TRIGGER pin permanently tied high or low and then in software trigger a detection (whenever required) and subsequently the switches will be automatically set and device type reported in Accessory Status register?

    Thanks

    Derren

  • 0 in reply to Derren Crome
    TI__Expert 5660 points

    Hi Derren,

    What is your specific application where you only want to trigger a detection manually? 

    Are you following the sequence below for manual control? It is important to set Auto DET Enable to '0' first, then I think when you enable Manual Switch Control and DET Trigger, the /DET_TRIGGER pin should not matter. 

    From what I can tell, the datasheet only covers what to do with the /DET_TRIGGER pin for the typical application where the automatic detection is used when /DET_TRIGGER pin is switched between the headphone jack and a pulldown resistor. So, I would like to help you figure out if you need the /DET_TRIGGER pin or not.

    According to the Device Settings Register field descriptions, the DET Trigger request bit will be ignored when /DET_TRIGGER pin is high, so I do not think that /DET_TRIGGER should be permanently tied high, but we should double check this when the Auto DET Enable is low vs high.

    You mentioned that pulling the /DET_TRIGGER pin permanently low did not work for you, so I want to ensure that you were using the proper sequence before we further troubleshoot.

    It's also important to point out that if you are NOT using I2C controls, certain pins need to be tied high or low. Check the Pin Functions table and ensure that these pins are not left floating.

    If you could send your manual control sequence and timing as well as a register map dump after every sequence step (for /DET_TRIGGER floating, pulled to GND, and pulled high), this should be very helpful to get to the bottom of it! If you can, a schematic/diagram could also help me. Feel free to send this offline if you want.

    Thanks in advance for this information!

    Best regards,
    Kate