Specifications

Product Technical Specification & Customer Design Guidelines
Interfaces
3.11.4.1.2 MIC1 Single-ended Connection Example
53
54
Audio
ADC
Z1*= 1100
O
typ
2.1 V typ
100nF
100nF
MIC1P
MIC1N
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WA_DEV_Q64_PTS_001-003 January 9, 2009
C1
L1
C2
WMP100
(Inside Q64)
60 AREF
Figure 15: Example of MIC1 input single-ended connection with LC filter
*:Z1 is from 200Hz to 4kHz. For more characteristics refer to chapter 3.11.1.1.1.
Internal input impedance value becomes 1100 Ω, due to the connection of MIC1N to
ground.
It is recommended to use the Q64 Wireless CPU
®
AREF pin for good ground
connection.
It is recommended to add L1 and C2 footprint to add a LC filter to reduce the TDMA
noise.
When not used, the filter can be removed by replacing L1 by a 0 Ω resistor and by
disconnecting C2, as the following schematic.
Audio
ADC
Z1*= 1100
O
typ
2.1V typ
100nF
100nF
MIC1P
MIC1N
53
54
C1
WMP100
(Inside Q64)
60 AREF
Figure 16: Example of MIC1 input single-ended connection without LC filter
*:Z1 is from 200Hz to 4kHz. For more characteristics refer to the chapter 3.11.1.1.1.