- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384930 > SSM-2122 (Analog Devices, Inc.) Dynamic Range Processors/Dual VCA PDF資料下載
參數(shù)資料
| 型號： | SSM-2122 |
| 廠商： | Analog Devices, Inc. |
| 英文描述： | Dynamic Range Processors/Dual VCA |
| 中文描述： | 動態(tài)范圍處理器/雙殼抗原 |
| 文件頁數(shù)： | 7/12頁 |
| 文件大?。?/td> | 371K |
| 代理商： | SSM-2122 |
SSM2120/SSM2122
REV. C
–7–
V+
LOG AV
4.7M
V–
+V
C
–V
C
SIGNAL
INPUT
SIGNAL
OUTPUT
200
2200pF
47
36k
36
10pF
TRANSMISSION
OR
STORAGE
MEDIUM
1μF
|I
IN
|
10k
REC
IN
39k
10k
V+
1k
R
C
1μF
V+
LOG AV
4.7M
V–
–V
C
+V
C
2200pF
47
36k
36k
10pF
1μF
|I
IN
|
10k
REC
IN
39k
10k
V+
1k
R
E
1μF
200
200
200
V–
V–
Figure 10. Companding Noise Rejection System
signal will be dependent on the noise of the current-to-voltage
converter amplifier if the expansion ratio is high enough.
As discussed in the Threshold Control section, the use of the
control circuit of Figure 6, including the R
PV
to V+ and two
diodes, yields positive unipolar control outputs.
COMPANDING NOISE REDUCTION SYSTEM
A complete companding noise reduction system is shown in
Figure 10. Normally, to obtain an overall gain of unity, the
value of R
C
is equal to R
E
. The values of R
C/E
will determine the
compression/expansion ratio.
Table II shows compression/expansion ratios ranging from 1.5:1
to full limiting with the corresponding values of R
C/E
.
An example of a 2:1 compression/expansion ratio is plotted in
Figure 11. Note that signal compression increases gain for low
level signals and reduces gain for high levels while expansion
does the reverse. The net result for the system is the same as the
original input signal except that it has been compressed before
being sent to a given medium and expanded after recovery. The
compression/expansion ratio needed depends on the medium
being used. As an extreme example, a household tape player
would require a higher compression/expansion ratio than a
professional stereo system.
INPUT SIGNAL LEVEL – dB
20
0
–80
–80
20
–60
O
–40
–20
0
–20
–40
–60
I
REF
≈
3μA
R
REF
= 4.7M
OVERALL
RESPONSE
2:1
EXPANSION
2:1
COMPRESSION
25dB
Figure 11. Companding Noise Reduction with 2:1
Compression/Expansion Ratio
Table II.
Gain
(Reduction
or Increase)
(dB)
Compressor
Only
Output Signal
Increase (dB)
Expander
Only
Output Signal
Increase (dB)
Input Signal
Increase (dB)
Compression/
Expansion Ratio
D
V
CONTROL
–
(mV/dB)
R
C/E
V
20
20
20
20
20
20
20
20
6.67
10.00
13.33
15.00
16.00
17.33
18.00
20.00
13.33
10.00
6.67
5.00
4.00
2.67
2.00
0
22.67
30.00
33.33
35.00
36.00
37.33
38.00
40.00
1.5:1
2:1
3:1
4:1
5:1
7.5:1
10:1
AGC*/Limiter
11,800
7,800
5,800
5,133
4,800
4,415
4,244
3,800
2.0
3.0
4.0
4.5
4.8
5.2
5.4
6.0
*AGC for Compression Only.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| SSM2120 | Dynamic Range Processors/Dual VCA |
| SSM2122 | Dynamic Range Processors/Dual VCA |
| SSM-2134 | LOW NOISE AUDIO OPERATIONAL AMPLIFIER |
| SSM2134 | LOW NOISE AUDIO OPERATIONAL AMPLIFIER |
| SSM-2404 | Quad Audio Switch |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SSM2122P | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Amplifier. Other |
| SSM2125 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Dolby Pro-Logic Surround Matrix Decoder |
| SSM-2125 | 制造商:AD 制造商全稱:Analog Devices 功能描述:DOLBY PRO-LOGIC SURROUND MATRIX DECODER |
| SSM2125A0011P | 制造商:Analog Devices 功能描述: |
| SSM2125A0019P | 制造商:Analog Devices 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。