Datasheet

MAX4649
45Ω, SPDT Analog Switch in SOT23-8
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leakage characteristics. Device operation is un-
changed, and the difference between V+ and V- should
not exceed 44V. These protection diodes are not rec-
ommended when using a single supply.
Off-Isolation at High Frequencies
In 50Ω systems, the high-frequency on-response of
these parts extends from DC to above 300MHz, with a
typical loss of -3.6dB. When the switch is turned off,
however, it behaves like a capacitor, and off-isolation
decreases with increasing frequency. This effect is
more pronounced with higher source and load imped-
ances. Above 5MHz, circuit board layout becomes criti-
cal. The graphs shown in the Typical Operating
Characteristics were taken using a 50Ω source and
load connected with BNC connectors.
t
R
< 20ns
t
F
< 20ns
50%
0
V
NO
LOGIC
INPUT
V-
-V
R
L
1000Ω
COM
GND
C
L
INCLUDES FIXTURE AND STRAY CAPACITANCE.
LOGIC
INPUT
NC
IN
t
TRANS
+3V
t
TRANS
V
O
V
NC
V+
NO
V
O
0.9V
NC
0.9V
NO
SWITCH
OUTPUT
MAX4649
+V
C
L
35pF
V
NC
V
NO
Figure 2. MAX4649 Transition Time
V+
COM
V-
NO_
V
g
V+
D1
D2
V-
Test Circuits/Timing Diagrams
Figure 1. Overvoltage Protection