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
 7 Terminal electrical interface specification
        7.1 Communication mode (terminal)
        7.2 Multimedia playback mode (terminal)
 8 Headset specification
        8.1 Communication mode (headset) for the communication mode              
        8.2 Multimedia playback mode (headset)
 9 Function requirements for terminals with the universal headset interface    
Annex A – Interpolation method for diffuse-field correction
Annex B – Recording procedure using a representative headset
Appendix I – Audio connectivity for sockets with four contact points
        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
Appendix II – Audio connectivity for sockets with four contact points (optional dimensions to accommodate terminal designs with curved edges)
Appendix III – Audio connectivity for sockets with three 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  
Appendix IV – Other considerations
       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
Bibliography