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GC868-DUAL EVK2 User Guide
1vv0300803 Rev.1- May 2009
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 28
of 55
11 Audio Accessories
The following tables show the suggested specification to obtain the best performance from
off-
the-shelf
accessories.
11.1 Headset
Nominal sensitivity
-45dBV
rms
/1Pa (+/- 3dB)
Line coupling
AC
Nominal Voltage
2V
Range of Using Voltage
(1÷10)V
Consumption Current
(150÷500 )
μ
A
Impedance
2,2K
Ω
Signal to Noise Ratio
56dB /1KHz/1Pa
(A curve)
Inner EMI capacitor between
terminals
10pF, 33pF
Table 2: Microphone electrical characteristics
Rated Input Power
5mW
Maximum Input Power
20mW
Coil Impedance
32
Ω
±
5
Ω
@ 1kHz
SPL
95
±
3 dB @ 1KHz/1mW sine
wave
Resonance frequency (Fo)
< 350Hz
Useful Bandwidth
Fo ÷ 8000 Hz @ -3dB
Table 3: Earpiece electrical characteristics