EG_GenLoc41e_1055_UG_003_UK
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Descriptions and non-contractual illustrations in this document are given as an indication only.
ERCOGENER reserves the right to make any modifications.
Dct_427_02
7.8.1 Microphone inputs
The microphone input is designed for a direct connection of the electret condenser micro. (for more details,
see the command AT+USPM).They already 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 1.5
kΩ.
The gain of the microphone inputs is internally adjusted by a differential amplifier and can be adjusted with
the command
AT+UMGC
(see the document "EG_EGM_CL_xxx_yy" of ERCOGENER). The amplifier has a
gain of 25.6 dB and a Bias generator that supplies an external voltage of 2 or 2.5V for the microphone Bias.
Pin description
Signal
Sub HD connector
Pins number
I/O
I/O type
Description
MICP
4
I
Analog
Positive input of Microphone
MICN
5
I
Analog
Negative input of Microphone
– 0V
7.8.2 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
SPKP
10
O
Analog
Positive output of loudspeaker
SPKN
15
O
Analog
Negative output of loudspeaker
* When the ANA2 option is present, the speaker audio output is available between SPKP (pin
10 of the sub D HD 15 points) and 0V.
In this case the audio power available is divided by 2 see § 8.2.3.2 Loudspeaker.
7.8.3 Buzzer outputs
The modem contains the EGM standard library (see the documents "EG_EGM_CL_xxx_yy" of
ERCOGENER); in this case, by default, the GenLoc 41e provides a Buzzer output on output 1 (instead of the
DCD) of the 15-pin Sub-D connector. This output provides a PWM output, and is used to drive a
Transducer
.
Pin description
Signal
Sub HD connector
Pin number
I/O
I/O type
Description
Buzzer
1
O
Analog
Output Buzzer