DG408DY-T1-E3/BKN Vishay, DG408DY-T1-E3/BKN Datasheet - Page 11

• Manufacturer Part Number: DG408DY-T1-E3/BKN
• Description: 8-Ch Multiplexer
• Manufacturer: Vishay

APPLICATIONS HINTS
Overvoltage Protection
A very convenient form of overvoltage protection consists of
adding two small signal diodes (1N4148, 1N914 type) in
series with the supply pins (see Figure 10). This
arrangement effectively blocks the flow of reverse currents.
It also floats the supply pin above or below the normal V+ or
V- value. In this case the overvoltage signal actually
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 http://www.vishay.com/ppg?70062.
Document Number: 70062
S-71155–Rev. G, 11-Jun-07
Enable In
Clock
(MUX On-Off Control)
In
8-Channel Sequential Multiplexer/Demultiplexer
NC
(Outputs)
Analog
Inputs
B
A
DM7493
r
01
IN
IN
+ 15 V
+ 15 V
r
02
GND
Q
Q
Q
Q
B
C
D
A
+ 15 V
S
S
S
S
S
S
S
S
A
NC
V+
1
2
3
4
5
6
7
8
0
A
Figure 10. Overvoltage Protection Using Blocking Diodes
GND
DG408
1
A
V
2
g
- 15 V
EN
V-
D
Analog
Output
S
X
(Input)
Reset Enable
Figure 11.
Clock
In
V+
V-
Differential 4-Channel Sequential Multiplexer/Demultiplexer
becomes the power supply of the IC. From the point of view
of the chip, nothing has changed, as long as the difference
VS - (V-) doesn’t exceed + 44 V. The addition of these diodes
will reduce the analog signal range to 1 V below V+ and 1 V
above V-, but it preserves the low channel resistance and low
leakage characteristics.
1N4148
1N4148
DG408
Differential
(Outputs)
Analog
Inputs
J
CLK
K
CLEAR
1/2 MM74C73
+ 15 V
GND
D
Q
Q
+ 15 V
NC
S
S
S
S
S
S
S
S
V+
1a
2a
3a
4a
1b
2b
3b
4b
A
0
GND
DG409
A
1
J
1/2 MM74C73
CLK
K
- 15 V
Vishay Siliconix
EN
V-
CLEAR
D
D
DG408/409
a
b
6
www.vishay.com
Differential
Q
Q
Outputs
(Inputs)
Analog
NC
11