The device has a 3.5mm AV-connector. The user can use it to connect any audio accessory or e.g. TV-out cable
to the phone. In-box headset (HS-43) is so-called Enhancement Control Interface (ECI) accessory. If the
connected cable is not ECI accessory, cable recognizing is based on impedance on the microphone line. If the
cable cannot be recognized, the user can select which accessory type is connected to the phone.
There are five Audio Control lines from Cellular Modem ASIC D2800 to control control audio and AV-connector
related electronics. Those signals and default stages of the signals are described in the following table.
Figure 65 Connector pin layout (Plug conductors from left to right HS EAR L, HS EAR R, HS MIC/Cntrl. and HS GND)
Page 7 –28
Table 17 AUDIOCTRL interface
Plug_det from AV-
Mic2P / head_det
Mic2P / Comp_Video
IHF amp N2120
Figure 64 AV connector component layout and pads
Copyright © 2008 Nokia. All rights reserved.
Default state / action
1.8V (VIO), grounded when 3.5mm plug
Default 0 (microphone line connected
to Mic2P). When 1, microphone line
connected to head_det -> ECI-detection
Default 0, (microphone line connected
to Mic2P). When 1, Composite Video
from APE connected to microphone
Default 0, IHF amplifier and
attenuation not used.