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MTX-Java-IoT | 2018/2
MTX © by MATRIX ELECTRONICA S.L.U.
SUPPORT:
SALES:
mtxm2m.com
8. Analog audio interface
Those MTX-Java-IoT models ordered with Audio option (A) have a 6-way 4-pole RJ connector, as shown
below, allowing a telephone handset to be plugged into the modem and 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-Java-IoT 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
1 2 3 4 5 6
PIN
SIGNAL
DIRECTION
DESCRIPTION
1
NC
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
NC