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SLES100 − DECEMBER 2003
Differential Section
The PCM1796 voltage outputs are followed by differential amplifier stages, which sum the differential signals for each
channel, creating a single-ended I/V op-amp output. In addition, the differential amplifiers provide a low-pass filter
function.
The op amp recommended for the differential circuit is the low-noise type.
C
1
2700 pF
R
1
820 Ω
V
CC
V
CC
C
3
C
11
0.1 µF
8200 pF
R
200 Ω
5
C
15
0.1 µF
C
22 pF
17
C
22 pF
19
7
5
R
220 Ω
R
7
7
2
3
8
6
3
−
+
I −
OUT
5
180 Ω
R
100 Ω
2
3
8
6
9
−
+
C
5
U
1
27000 pF
NE5534
U
4
3
NE5534
4
R
4
R
8
180 Ω
C
12
0.1 µF
220 Ω
R
6
200 Ω
C
16
0.1 µF
C
4
V
EE
8200 pF
V
EE
C
2
2700 pF
R
2
820 Ω
V
CC
C
13
0.1 µF
C
22 pF
18
7
5
2
3
8
6
−
+
I +
OUT
U
2
NE5534
4
V
V
= 15 V
= −15 V
= 50 kHz
CC
EE
C
14
0.1 µF
f
c
V
EE
Figure 36. Measurement Circuit for PCM
34
BB [ BURR-BROWN CORPORATION ]
