Data Sheet

FSC-BT1006A Datasheet
Shenzhen Feasycom Technology Co.,Ltdwww.feasycom.com
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A digital gain stage
Figure 11: Audio Input Gain
ADC Pre-amplifier and analog/digital Gain
The gain of the ADC inputs can be configured in the range of -27 dB to 63.5 dB steps, making it suitable for line
andmicrophone input levels. 0 dB is 1600 mV pk-pk input.
The ADC input impedance is nominal 6 kΩ except when 0 dB pre-amplifier gain is selected when it becomes 12 kΩ.
If the input pre-amplifier is disabled, the input impedance varies between 6 kΩ and 34 kΩ, depending on
gainselection. In normal operation, the input pre-amplifier is enabled.
Calls connected by the VM stream automatically select the distribution of gain within the ADC for best
performance.Alternatively,the individual gain stages can be set.
ADC Digital Gain
A digital gain stage inside the ADC varies from -24dB to 21.5dB, see following table. There is also a fine gain
interface with a 9-bit gain setting allowing gain changes in 1/32 steps, for more infomation contact Feasycom.
The firmware controls the audio input gain.
Table 6: ADC Audio Input Gain Rate
Digital Gain Selection
Value
ADC Digital Gain Setting(dB)
Digital Gain Selection
Value
ADC Digital Gain Setting(dB)
0
0
8
-24
1
3.5
9
-20.5
2
6
10
-18
3
9.5
11
-14.5
4
12
12
-12
5
15.5
13
-8.5
6
18
14
-6
7
21.5
15
-2.5
ADC Digital IIR Filter