dg641 Vishay, dg641 Datasheet - Page 8

• Manufacturer Part Number: dg641
• Description: Low On-resistance Wideband/video Switches
• Manufacturer: Vishay

DG641/642/643
Vishay Siliconix
Device Description
The DG641/642/643 switches offer true bidirectional switching
of high frequency analog or digital signals with minimum signal
crosstalk, low insertion loss, and negligible non-linearity
distortion and group delay.
Built on the Siliconix D/CMOS process, these switches provide
excellent off-isolation with a bandwidth of around 500 MHz.
The silicon-gate D/CMOS processing also yields fast
switching speeds.
An on-chip regulator circuit maintains TTL input compatibility
over the whole operating supply voltage range shown, easing
control logic interfacing.
www.vishay.com FaxBack 408-970-5600
4-8
10
R
Generator
IN
Signal
75
V
S
S
S
S
1
2
3
4
DG641
(a)
“1”
D
D
D
D
1
2
3
4
Generator
Signal
50
FIGURE 5. All Hostile Crosstalk – X
R
L
R
L
FIGURE 6. Bandwidth
R
L
75
V
R
S
OUT
L
Circuit layout is facilitated by the interchangeability of source
and drain terminals.
Frequency Response
A single switch on-channel exhibits both resistance [r
and capacitance [C
attenuation effect on the analog signal – which is frequency
dependent (like an RC low-pass filter). The –3 dB bandwidth
of the DG641/642/643 is typically 500 MHz (into 50
V+
V–
–3 V
D
+15 V
10
Generator
TALK(AH)
R
Signal
IN
75
50
R
L
V
X
S(on)
TALK(AH)
V
OUT
]. This RC combination has an
S
S
1
2
DG642
20 log
“0”
(b)
10
D
D
S-52433—Rev. E, 06-Sep-99
1
2
V
Document Number: 70058
OUT
V
R
L
DS(on)
V
R
75
OUT
L
]