TOBY-L4 series - System Integration Manual
UBX-16024839 - R04
Design-in
Page 103 of 143
TOBY-L4 series
MIC1_P
R1
R2
R4
MIC1_N
R3
C1
MIC_BIAS
C2
C3
D1
L2
L1
C5
C4
Microphone
Connector
MIC1
J1
D2
MIC2_P
R6
R8
MIC2_N
R7
C6
MIC_GND
C7
C8
D3
L4
L3
C9
C10
Microphone
Connector
MIC2
J2
D4
R5
Figure 60: Application circuit connecting the analog audio interface to two external electret microphones
Reference
Description
Part Number – Manufacturer
C1, C6
10 µF Capacitor Ceramic X5R 0603 20% 6.3 V
GRM188R60J106ME47 – Murata
C2, C3, C7, C8
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R71C104KA88 – Murata
C4, C5, C9, C10
27 pF Capacitor Ceramic C0G 0402 5% 25 V
GRM1555C1H270JA01 – Murata
D1, D2, D3, D4
Low Capacitance ESD Protection
CG0402MLE-18G - Bourns
J1, J2
Microphone Connector
Various Manufacturers
L1, L2, L3, L4
82 nH Multilayer inductor 0402
(self resonance frequency ~1 GHz)
LQG15HS82NJ02 – Murata
MIC1, MIC2
2.2 k
Electret Microphone
Various Manufacturers
R1, R5
1.5 k
Resistor 0402 5% 0.1 W
RC0402JR-071K5L – Yageo Phycomp
R2, R3, R4,
R6, R7, R8
2.2 k
Resistor 0402 5% 0.1 W
RC0402JR-072K2L – Yageo Phycomp
Table 44: Example of components for connecting the analog audio interface to two electret microphones