u-blox LEON-G100 ECALL, Руководство по системной интеграции

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LEON-G100 / LEON-G200 - System Integration Manual
GSM.G1-HW-09002-G3 Preliminary System description
Page 62 of 125
1.10.1.3 Handset mode
Handset mode is the default audio operating mode of LEON-G100 / LEON-G200 modules. In this mode the main
uplink audio path is “Handset microphone”, the main downlink audio path is “Normal earpiece” (refer to
u-blox
AT Commands Manual [2]; AT+USPM command: <main_uplink>, <main_downlink> parameters).

Handset microphone must be connected to inputs
MIC_BIAS1/MIC_GND1

Handset receiver must be connected to output HS_P
Figure 36 shows an example of an application circuit connecting a handset (with a 2.2 k Ω electret microphone
and a 32 Ω receiver) to the LEON-G100 / LEON-G200 modules. The following actions should be done on the
application circuit:

Mount a series capacitor on the HS_P line to decouple the bias

Mount a 10 µF ceramic capacitor (e.g. Murata GRM188R60J106M) if connecting a 32 Ω receiver, or a load
with greater impedance (such as a single ended analog input of a codec). Otherwise if a 16 Ω receiver is
connected to the line, a ceramic capacitor with greater nominal capacitance must be used: a 22 µF series
capacitor (e.g. Murata GRM21BR60J226M) is required

Mount a 82 nH series inductor (e.g. Murata LQG15HS82NJ02) on each microphone line and a 27 pF bypass
capacitor (e.g. Murata GRM1555C1H270J) on all audio lines to minimize RF coupling and TDMA noise
LEON-G100 /
LEON-G200
C1
AUDIO
HANDSET
CONNECTOR
C2 C3
J1
4
3
2
1 L1
L2
37
HS_P
43 MIC_GND1
44
MIC_BIAS1
C4
D1
Figure 36: Handset connector application circuit
Reference Description Part Number - Manufacturer
C1, C2, C3 27 pF Capacitor Ceramic COG 0402 5% 25 V GRM1555C1H270JZ01 - Murata
C4 10 µF Capacitor Ceramic X5R 0603 20% 6.3V GRM188R60J106M - Murata
L1, L2 82 nH Multilayer inductor 0402
(self resonance frequency ~1 GHz) LQG15HS82NJ02 - Murata
J1 Audio Handset Jack Connector, 4Ckt (4P4C) 52018-4416 - Molex
D1 Varistor Array for ESD protection CA05P4S14THSG - EPCOS
Table 22: Example of components for handset connection
1.10.1.4 Headset mode
The audio path is automatically switched from handset mode to headset mode when a rising edge is detected by
the module on
HS_DET pin. The audio path returns to the handset mode when the line returns to low level.
In headset mode the main uplink audio path is “Headset microphone”, the main downlink audio path is “Mono
headset” (refer to
u-blox AT Commands Manual [2]; AT+USPM command: <main_uplink>, <main_downlink>
parameters).
The audio path used in headset mode:

Headset microphone must be connected to MIC_BIAS2/MIC_GND2

Headset receiver must be connected to
HS_P