Sony Ericsson GR47/GR48 Integrator's Manual page 31

5.7.3 Microphone Signals
LZT 123 7589 R1A
5. SYSTEM CONNECTOR INTERFACE
Parameter
Output Capacitance
Levels (THD < 5 %)
Pin Speaker signals
53 MICP
54 MICN
MICP and MICN are balanced differential microphone input pins. These
inputs are compatible with an electret microphone. The microphone
contains an FET buffer with an open drain output, which is supplied with
at least +2 V relative to ground by the radio device as shown below.
GR47
Figure 5.5 Microphone connections to the radio device
Drive capability into 5 k
(0.3 - 3.5 kHz)
Drive capability into 1.5 k
(0.3 - 3.5 kHz)
Drive capability into 150
(at 1 kHz)
Dir Function
I Microphone positive input
I Microphone negative input
1k
2 - 2.5V
@ 1mA
68nF
CODEC
68nF
1k
AGND
Limit
2.2 µF ±10 %
> 2.4 V
p-p
> 2.2 V
p-p
> 1.3 V
p-p
MICP
MICN
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