Rec. ITU-T P.381 (10/2020) Technical requirements and test methods for the universal wired headset or headphone interface of digital mobile terminals
Summary
History
FOREWORD
Table of Contents
1 Scope
2 References
3 Definitions
     3.1 Terms defined elsewhere
     3.2 Terms defined in this Recommendation
4 Abbreviations and acronyms
5 General description
6 Physical characteristics
     6.1 General rules
     6.2 Pin assignments
          6.2.1 Recommended pin assignment
          6.2.2 Alternative pin assignment
7 Terminal electrical interface specification
     7.1 Communication mode (terminal)
          7.1.1 Test set-up for the communication mode (terminal)
               7.1.1.1 Input and output characteristics of the test system for connecting to the headset connector
               7.1.1.2 Test signals and test signal levels
          7.1.2 Delay for the communication mode (terminal)
               7.1.2.1 Requirements
               7.1.2.2 Test
                    7.1.2.2.1 Test of overall terminal delay in Send
                    7.1.2.2.2 Test of overall terminal delay in Receive
          7.1.3 Level in Send for nominal speech input level for the communication mode (terminal)
               7.1.3.1 Requirements
               7.1.3.2 Test
          7.1.4 Level in Receive for nominal speech input level for the communication mode (terminal)
               7.1.4.1 Requirements
               7.1.4.2 Test
          7.1.5 Level in Send for low and high speech input levels for the communication mode (terminal)
               7.1.5.1 Requirements
               7.1.5.2 Test
          7.1.6 Linearity in Receive for the communication mode (terminal)
          7.1.7 Sending frequency response for the communication mode (terminal)
               7.1.7.1 Requirements
               7.1.7.2 Test
          7.1.8 Receiving frequency response for the communication mode (terminal)
               7.1.8.1 Requirements
               7.1.8.2 Test
          7.1.9 Sidetone loss for the communication mode (terminal)
               7.1.9.1 Requirements
               7.1.9.2 Test
          7.1.10 Sidetone delay for the communication mode (terminal)
               7.1.10.1 Requirements
               7.1.10.2 Test
          7.1.11 Noise in Send for the communication mode (terminal)
               7.1.11.1 Requirements
               7.1.11.2 Test
          7.1.12 Noise in Receive for the communication mode (terminal)
               7.1.12.1 Requirements
               7.1.12.2  Test
          7.1.13 Sending distortion for the communication mode (terminal)
               7.1.13.1 Requirements
               7.1.13.2 Test
          7.1.14 Receive distortion for the communication mode (terminal)
               7.1.14.1 Requirements
               7.1.14.2 Test
          7.1.15 Noise cancellation test in Send for the communication mode (terminal)
               7.1.15.1 Requirements
               7.1.15.2 Test
          7.1.16 One-way speech quality in Send for the communication mode (terminal)
               7.1.16.1 Requirements
               7.1.16.2 Test
          7.1.17 One-way speech quality in Receive for the communication mode (terminal)
               7.1.17.1 Requirements
               7.1.17.2 Test
          7.1.18 Terminal coupling loss for the communication mode (terminal)
               7.1.18.1 Requirements
               7.1.18.2 Test
          7.1.19 Temporal echo effects for the communication mode (terminal)
               7.1.19.1 Requirements
               7.1.19.2 Test
          7.1.20 Double talk performance for the communication mode (terminal)
               7.1.20.1 Attenuation range in the Send direction during double talk
                    7.1.20.1.1 Requirements
                    7.1.20.1.2 Test
               7.1.20.2 Attenuation range in the Receive direction during double talk
                    7.1.20.2.1 Requirements
                    7.1.20.2.2 Test
               7.1.20.3 Detection of echo components during double talk
                    7.1.20.3.1 Requirements
                    7.1.20.3.2 Test
          7.1.21 Activation in Send for the communication mode (terminal)
               7.1.21.1 Requirements
               7.1.21.2 Test
     7.2 Multimedia playback mode (terminal)
          7.2.1 Test set-up for the multimedia playback mode (terminal)
               7.2.1.1 Input and output characteristics of the test system for connecting to the headset connector
               7.2.1.2 Test signals and test signal levels
          7.2.2 Output level for the multimedia playback mode (terminal)
               7.2.2.1 Requirements
               7.2.2.2 Test
          7.2.3 Frequency response for the multimedia playback mode (terminal)
               7.2.3.1 Requirements
               7.2.3.2 Test
          7.2.4 Noise for the multimedia playback mode (terminal)
               7.2.4.1 Requirements
               7.2.4.2 Test
          7.2.5 Distortion for the multimedia playback mode (terminal)
               7.2.5.1 Requirements
               7.2.5.2 Test
          7.2.6 Receiving crosstalk for the multimedia playback mode (terminal)
               7.2.6.1 Requirements
               7.2.6.2 Test
8 Headset specification
     8.1 Communication mode (headset) for the communication mode
          8.1.1 Test set-up (headset)
               8.1.1.1 Input and output characteristics of the test system for connecting the headset
               8.1.1.2 Test signals and test signal levels
               8.1.1.3 Positioning of the headsets
               8.1.1.4 Calibration of HATS
          8.1.2 Sensitivity in Send (headset)
               8.1.2.1 Requirements
               8.1.2.2 Test
          8.1.3 Sensitivity in Receive (headset)
               8.1.3.1 Requirements
               8.1.3.2 Test
          8.1.4 Sending frequency response (headset)
               8.1.4.1 Requirements
               8.1.4.2 Test
          8.1.5 Receiving frequency response (headset)
               8.1.5.1 Requirements
               8.1.5.2 Test
          8.1.6 Idle channel noise in Send (headset)
               8.1.6.1 Requirements
               8.1.6.2 Test
          8.1.7 Distortion in Send (headset)
               8.1.7.1 Requirements
               8.1.7.2 Test
          8.1.8 Coupling loss (headset)
               8.1.8.1 Requirements
               8.1.8.2 Test
     8.2 Multimedia playback mode (headset)
          8.2.1 Test set-up (headset)
               8.2.1.1 Input and output characteristics of the test system for connecting the headset
               8.2.1.2 Test signals and test signal levels
               8.2.1.3 Positioning of the headsets
               8.2.1.4 Position and calibration of HATS
          8.2.2 Sensitivity for the multimedia playback mode (headset)
               8.2.2.1 Requirements
               8.2.2.2 Test
          8.2.3 Distortion for the multimedia playback mode (headset)
               8.2.3.1 Requirements
               8.2.3.2 Test
          8.2.4 Receiving crosstalk (headset)
               8.2.4.1 Requirements
               8.2.4.2 Test
9 Function requirements for terminals with the universal headset interface
     I.1 2.5 mm diameter plug connector with four poles
     I.2 2.5 mm diameter socket connector with four contact points
     I.3 3.5 mm diameter plug connector with four poles
     I.4 3.5 mm diameter socket connector with four contact points
     III.1 2.5 mm diameter plug connector with three poles
     III.2 2.5 mm diameter socket connector with three contact points
     III.3 3.5 mm diameter plug connector with three poles
     III.4 3.5 mm diameter socket connector with three contact points
     IV.1 Filter recommendation
     IV.2 Electrostatic discharge
     IV.3 Microphone basics – background
     IV.4 Vcc voltage for microphone bias
     IV.5 DC resistance of microphone