Shanghai ZhiWu Communication Technology Co. Ltd MX680 用户手册
MX680 Hardware Design V2.00
4.9.3 Earphone Interfaces Configuration
Figure 33: Earphone reference circuit
4.9.4 Audio Electronic Characteristic
Table 15: Microphone input characteristics
Parameter
Min
Typ
Max
Unit
Working voltage
1.2
1.5
2.0
V
Working current
200
-
500
uA
Input impedance(differential)
1.2
2.2
KΩ
Microphone biasing voltage
1.9
2.2
V
SINAD
THD <1% at
F=1KHz; pre-amp
gain = 20 dB; PGA
gain = 14 dB
F=1KHz; pre-amp
gain = 20 dB; PGA
gain = 14 dB
15.9
mVrms
THD<5%at F=1KHz;
pre-amp gain = 0
dB; PGA gain = 0 dB
pre-amp gain = 0
dB; PGA gain = 0 dB
740
mVrms
Table 16: Audio output characteristics
Parameter
Conditions
Min
Max
Max
Unit
Normal output(SPK)
RL=32Ω
THD=0.1%
THD=0.1%
-
91
-
mW
RL=8Ω
500
850
mW
MX680 Hardware Design 44 / 58