MTX-HSPA-PH8-P+G
www.mtxm2m.com
www.matrix.es
2014/11 v2.0
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MTX Terminals® by MATRIX ELECTRONICA S.L.U
4.4
Audio connector
A 6-way 4-pole RJ connector, as shown below, allows a telephone handset to be plugged into the
modem, giving access to the microphone and earpiece signals. The connector may also be used to
drive other analog audio sub-systems or devices.
The audio interface provides one analog input for a microphone and one analog output for an
earpiece.
The microphone input and the earpiece output are balanced
For electret microphones a supply source is implemented
The MTX-HSPA-PH8-P+G is pre-configured to work with a range of handsets, the audio
interface is flexible and its performance can be configured, using AT commands, to match a
particular handset or audio subsystem
Earpiece outputs are short-circuit protected
To suit the different types of accessories, the audio interfaces can be configured for different audio
modes via the AT^SNFS command. The electrical characteristics of the voiceband part vary with the
audio mode. For example, sending and receiving amplification, sidetone paths, noise suppression etc.
depend on the selected mode and can be altered with AT commands (except for mode 1).
Pin
Signal
Direction
Description
1
Not connected
2
MICN
Input
Microphone negative input
3
EPN
Output
Earpiece negative output
4
EPP
Output
Earpiece positive output
5
MICP
Input
Microphone positive input
6
Not connected
