• Resolved

TS3A227E: about detect CTIA and OMTP

Part Number: TS3A227E

Hi,

Detection error has occurred in the customer's circuit.
Could you tell me about detect CTIA and OMTP?
The following contents are described in the data sheet.
”This is done by directly connecting the microphone bias and the ground connections to the sleeve and ring2 pins of the audio jack. For the end user this leaves a headset standard as fully unsupported.”

However, There is no description of the discrimination method between CTIA and OMTP.
How does TS3A227E distinguish between CTIA and OMTP?
Please tell me about the detection internal circuit.

Detection error occurs in the customer's application when the insertion / removal test is repeated plural times.
Therefore, please explain what kind of method and what TS3A227E is detecting (voltage / current / resistor).
And Should customers process MUTE etc. at the time of insertion / removal?

Best Regards,
Yusuke/Japan Disty



  • Tsukui-san,

    These e2e posts and application notes give some more information on how TI's audio jack switches detect the difference between different types of headsets.

    I will continue to look through the schematics when I return to the office.

    Thank you,

    Adam

  • In reply to Adam Torma:

    Hi Adam-san,

    Thank you for the quick reply in out of office timing.
    I read the URL link description.

    ”f the resistance R2 = Rsleeve than the device will detect 3-pole
    If the resistance R2 < Rsleeve than the device will detect Standard
    If the resistance R2 > Rsleeve than the device will detect OMTP"

    TS3A227E converts voltage to register values and senses R2 and Rsleeve.
    Is it correct in my understanding?
    If so,Could you tell me how to voltage sensing and convert voltage to register values?
    CTIA / OMTP detection error has occurred in the customer's circuit.
    Therefore, the customer wants detection method detailed information.

    "I will continue to look through the schematics when I return to the office."
    →Thank you for your kind support.
        Hope to hear from you soon.

    Best Regards,
    Yusuke/Japan Disty




  • In reply to Tsukui Yusuke:

    Yusuke-san, 

    There is a ADC internal to the TS3A227E that can convert the voltage to a register values.  

    I will continue the discussion on the schematics over email. 

    Thank you, 

    Adam