Figure 6. A Precision Amplifier with Digitally Programmable Inputs and Gains
Gain =
Gain 1 (x 1)
Gain 2 (x 10)
Gain 3 (x 100)
Gain 4 (x 1000)
- 15 V
+ 15 V
- 15 V
GND
DG419
30 pF
+ 15 V
+ 15 V
- 15 V
DG308B
Logic High = Switch On
+
-
LM101A
R
F
+ R
g
R
g
V
IN1
V
IN2
CH
R
F1
18 k
R
F1
9.9 k
R
F1
100 k
R
g3
100
R
g2
100
R
g1
2 k
V+
V-
GND V-
+ 5 V
V
L
Figure 7. Sample-and-Hold
LM101A
+ 15 V
- 15 V
30 pF
15 V
- 15 V
V+
V-
DG309B
50 pF
1000 pF
J202
J500
J507
+ 15 V
2N4400
- 15 V
V
IN
V
OUT
1 k
200
5 M
5.1 M
Aquisition T ime = 25 µs
Aperature T ime = 1 µs
Sample to Hold Of fset = 5 mV
Droop Rate = 5 mV/s
Logic Input
Low = Sample
High = Hold
-
+
Document Number: 70047
S11-0303-Rev. G, 28-Feb-11
www.vishay.com
9
Vishay Siliconix
DG308B, DG309B
APPLICATIONS
Vishay Siliconix maintains worldwide manufacturing capability. Products may be manufactured at one of several qualified locations. Reliability data for Silicon
Technology and Package Reliability represent a composite of all qualified locations. For related documents such as package/tape drawings, part marking, and
reliability data, see www.vishay.com/ppg?70047
.
Figure 8. Active Low Pass Filter with Digitally Selected Break Frequency
TTL
Control
150 pF
1500 pF
+ 15 V
DG309B
GND
30 pF
LM101A
+ 15 V
- 15 V
Frequency – Hz
1 1 0 100 1 k 10 k 100 k 1 M
- 40
0
160
120
80
V oltage Gain dB
f
C4
Select
f
C3
Select
f
C2
Select
f
C1
Select
R
1
= 10 k
R
2
= 10 k
R
3
= 1 M
V
OUT
V
1
V-
C
4
C
3
C
2
C
1
0.015 μF
0.15 µF
- 15 V
-
+
40
f
C1
f
C2
f
C3
f
C4
f
L1
f
L2
f
L3
f
L4
A
L
(V oltage Gain Below Break Frequency) = = 100 (40 dB)