Sony Ericsson TT4031 (SE-GM29) - Manual (Page 31)

Owner’s Manual Rev 1.0 Page 31 of 31
Audio signal descriptions are listed below:
Pin Signal Dir Description
1 MICN I Microphone negative input
2 BEARN O Earpiece negative output
3 BEARP O Earpiece positive output
4 MICP I Microphone positive input
MICP and MICN are balanced differential microphone input signals. These
inputs are compatible with an electret microphone.
BEARP and BEARN are the speaker output signals. These are differential
mode outputs. The electrical characteristics are given in the table below.
Parameter Limit
Output level (differential) 4.0 V
pp
Output level (dynamic load = 32 Ω) 2.8 V
pp
Distortion at 1 kHz and maximum output level 5 %
Offset, BEARP to BEARN ± 30 mV
Ear-piece mute-switch attenuation 40 dB
The following table shows the ear piece impedances that can be connected
to BEARP and BEARN.
Ear piece model Impedance Tolerance
Dynamic ear piece [32 Ω+ 800 µH] // 100 pF ± 20 %
Dynamic ear piece [150 Ω+ 800 µH] // 100 pF ± 20 %
Piezo ear piece 1 kΩ+ 60 nF ± 20 %
Compliance with AMR may be required by certain
network operators.