Specifications

Telit GE864 and GC864
Product Description
80273ST10008A Rev. 3 - 10/02/06
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2.16 Audio levels specifications
The audio of the GE864 / GC864 is organized into two main paths:
- internal path (called also MT)
- external path (called also HF)
These two paths are meant respectively for handset and headset/hands-free use. The GE864 /
GC864 has a built in echo canceller and a noise suppressor, tuned separately for the two audio
paths; for the internal path the echo canceller parameters are suited to cancel the echo generated
by a handset, while for the external audio path they are suited for a hands-free use.
For more information on the audio refer to the Hardware User Guide.
The following table reports all the audio level specifications.
Microphone characteristics
Internal audio mic. input External audio mic. input
Line coupling
AC (100nF cond.) AC (100nF cond.)
Line type
Balanced Balanced
Differential input resistance
50kΩ 50kΩ
Line nominal sensitivity 50mV
rms
±2dB 3mV
rms
±2dB
Max input voltage 360mV
rms
22mV
rms
Microphone nominal sensitivity
– Analog Gain suggested
-45dB
Vrms/Pa
±2dB / +24dB -45dB
Vrms/Pa
±2dB / +10dB
Echo canceller type handset Car kit hands free
Speaker characteristics
Internal audio ear. output External audio ear. output
Line coupling DC DC
Line type
Bridged Bridged
Speaker impedance
≥ 16Ω ± 5% @ 1kHz ≥ 16Ω ± 5% @ 1kHz
Minimum load impedance
15Ω 15Ω
Signal bandwidth 150-8000 Hz @ -3dB 150-8000 Hz @ -3dB
Maximum output 1,3 V
rms
1,3 V
rms
Maximum power output
80mW/16Ω 80mW/16Ω
Volume level steps (SW) -2dB -2dB
Number of volume steps (SW) 14 14