User guide

EG_GenPro2xe_1003_UG_005_UK Page 45 / 63
Descriptions and non-contractual illustrations in this document are given as an indication only.
ERCO&GENER reserves the right to make any modifications.
Dct_427_00
7.9.1 Microphone inputs
The microphone inputs are assembled in differential to reduce the noise in common mode and the TDMA
noise.
They include the functionality for a microphone like Electret (0.5 mA and 2 Volts) and they are ESD
protected. This Electret microphone can be directly connected to these inputs allowing an easy connection to
a telephone handset.
The microphone impedance is around 36 k.
The gain of the microphone inputs is internally adjusted by a differential amplifier and can be adjusted with
the command AT+PREAMP (see the document "EG_EGM_CL_xxx_yy" of ERCO & GENER). The amplifier
has a gain of 25.6 dB and a Bias generator that supplies an external tension of 2 or 2.5V for the microphone
Bias.
Pin description
Signal
Sub HD connector
Pins number
I/O I/O Type Description
CMIC2P 4 E Analog Microphone positive input
CMIC2N 5 E Analog Microphone negative input
7.9.2 Loud-speaker outputs (Speaker)
The outputs are assembled in differential to reduce the noise in common mode and the TDMA noise.
These outputs can be directly connected to a loudspeaker.
Pin description
Signal
Sub HD connector
Pins number
I/O I/O Type Description
CSPK2P 10 S Analog Loudspeaker positive output
CSPK2N 15 S Analog Loudspeaker negative output
7.9.3 Buzzer output
In option the le GenPro 2xe provides a Buzzer output on output 1 (instead of the DCD) of the 15-pin Sub-D
connector. This output provides a frequency, and is used to drive a Transducer.