User's Manual

LISA-U1/LISA-H1 series - System Integration Manual
3G.G2-HW-10002-2 Advance Information System description
Page 68 of 116
Mount an 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.
The physical width of the audio outputs lines on the application board must be wide enough to
minimize series resistance.
C1 C2
C3
L1
39
MIC_N
53
SPK_P
40
MIC_P
54
SPK_N
D1
Microphone
Connector
D2
INOUT
GND
Low Noise
LDO Regulator
U1
R4
R1
C6
R3R2
C5
2V5
Sense lines connected to GND in one star point
C4
SPK
L2
MIC
Speaker
Connector
OUT+
IN+
GND
VMAIN
U2
OUT-
IN-
C8
C9
R5
R6
VDD
C11C10
LISA-U120/U130
Audio
Amplifier
J1
J2
VMAIN
C7
Figure 40: Hands-free mode application circuit
Reference
Description
Part Number - Manufacturer
C1, C2, C3, C4
27 pF Capacitor Ceramic COG 0402 5% 25 V
GRM1555C1H270JZ01 - Murata
C5, C6, C7, C10
10 µF Capacitor Ceramic X5R 0603 20% 6.3 V
GRM188R60J106ME47 - Murata
C8, C9
47 nF Capacitor Ceramic X7R 0402 10% 16V
GRM155R71C473KA01 - Murata
C11
100 nF Capacitor Ceramic X5R 0402 10% 10V
GRM155R71C104KA01 - Murata
D1, D2
Low Capacitance ESD Protection
USB0002RP or USB0002DP - AVX
J1
Microphone Connector
J2
Speaker Connector
L1, L2
82nH Multilayer inductor 0402
(self resonance frequency ~1 GHz)
LQG15HS82NJ02 - Murata
MIC
2.2 k Electret Microphone
R1, R2, R3, R4
2.2 kΩ Resistor 0402 5% 0.1 W
RC0402JR-072K2L - Yageo Phycomp
R5, R6
0 Ω Resistor 0402 5% 0.1 W
RC0402JR-070RL - Yageo Phycomp
SPK
8  Loudspeaker
U1
Low Noise LDO Linear Regulator 2.5 V 300 mA
LT1962EMS8-2.5#PBF- Linear Technology
U2
Filter-less Mono 2.8 W Class-D Audio Amplifier
SSM2305CPZ - Analog Devices
Table 29: Example of components for hands-free connection