DG642DY Vishay, DG642DY Datasheet - Page 9
DG642DY
Manufacturer Part Number
DG642DY
Description
Video Switch ICs SPDT Analog Switch
Manufacturer
Vishay
Datasheet
1.DG642DJ-E3.pdf
(11 pages)
Specifications of DG642DY
Number Of Switches
Single
On Resistance (max)
8 Ohms
On Time (max)
100 ns
Off Time (max)
60 ns
Supply Voltage (max)
21 V
Maximum Operating Temperature
+ 85 C
Minimum Operating Temperature
- 40 C
Package / Case
SOIC-8 Narrow
Maximum Power Dissipation
300 mW
Mounting Style
SMD/SMT
Supply Current
3.5 mA
Switch Configuration
SPDT
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
DG642DY
Manufacturer:
EL
Quantity:
20 000
Company:
Part Number:
DG642DY-T1-E3
Manufacturer:
MINI
Quantity:
300
APPLICATIONS
Document Number: 70058
S11-0154-Rev. F, 31-Jan-11
C
C
1
2
= 10 µ F Tantalum
= 0.1 µ F Ceramic
75
CH
S
S
S
S
1
2
3
4
1
Figure 7. Supply Decoupling
75
CH
2
75
- 3 V
V+
V-
CH
DG64X
+ 15 V
C
C
3
1
1
+
+
75
CH
TTL Channel Select
GNDs
Figure 8. 4 by 1 Video Multiplexing Using the DG641
4
C
C
2
2
D
D
D
D
1
2
3
4
- 3 V
V+
V-
DG641
+ 15 V
Board Layout
PCB layout rules for good high frequency performance must
also be observed to achieve the performance boasted by
these analog switches. Some tips for minimizing stray effects
are:
1.
2.
3.
Figure 8 shows a 4-channel video multiplexer using a
DG641.
In Figure 9, two coax cables terminated on 75 bring two
video signals to the DG642 switch. The two drains tied
together lower the on-state capacitance. An Si582 video
amplifier drives a double terminated 75 cable. The double
terminated coax cable eliminates line reflections.
Use extensive ground planes on double sided PCB,
separating adjacent signal paths. Multilayer PCB is
even better.
Keep signal paths as short as practically possible,
with all channel paths of near equal length.
Careful arrangement of ground connections is also
very important. Star connected system grounds
eliminate signal current, flowing through ground path
parasitic
channels.
250
DG641, DG642, DG643
+
-
resistance,
A = 2
250
Si582
DIS
from
Vishay Siliconix
75
coupling
www.vishay.com
between
9