Hardware+Design V1.07

Smart Machine Smart Decision
Note: SIM5320 has integrated MIC bias circuit. There is no need to pull the MIC1P and MIC1N up to the external power,
just connect it to microphone. MIC1P and MIC1N must be differential lines.
3.4.3 Audio Parameter Characteristic
Main audio parameters can be changed to satisfy users’ requirement. Here primary register parameters and
related description are listed. User can adjust them through AT command. For more detail please refers to
Audio Application Document.
Table 14: Audio parameter
Parameter Influence to Range Gain range Calculation AT command
micAmp1
MICP/MICN
analogue amplifier
gain before ADC
0…1 0…24dB 2 steps AT+CMICAMP1
txVol
Digital gain of input
signal after ADC
0,
1...65535
Mute,
-84...+12dB
20 * log
(txVol/
16384)
AT+CTXVOL
txGain
Digital gain of input
signal after
summation of
sidetone
0,
1...65535
Mute,
-84...+12dB
20 * log
(txGain/
16384)
AT+CTXGAIN
txFilter
Input PCM 13-tap
filter parameters, 7
values
0...65535 ---
MATLAB
calculate
AT+CTXFTR
rxGain
Digital gain of
output signal after
summation of
sidetone
0,
1...65535
Mute,
-84...+12dB
20 * log
(rxGain/
16384)
AT+CRXGAIN
rxVol
Digital Volume of
output signal after
speech decoder,
before summation of
sidetone and DAC
-300…300 dbm
-300…300d
bm
AT+CLVL
AT+CVLVL
AT+CRXVOL
stGain
Digital attenuation
of sidetone
0, 1...65535
Mute,
-96...0dB
20 * log
(stGain/
16384) -12
AT+SIDET
rxFilter
Output PCM 13-tap
filter parameters, 7
values
0...65535 ---
MATLAB
calculate
AT+CRXFTR
Note: If users require better experience on audio, users should modify these parameters according to their own electronic
SIM5320_Hardware Design_V1.07 2012-09-21
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