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Figure A illustrates use of the Analog Switch. The 0–
to–5 volt digital control signal is used to directly control a
5 volt peak–to–peak analog signal.
The digital control logic levels are determined by V DD and
V SS . The V DD voltage is the logic high voltage, the V SS volt-
age is logic low. For the example, V DD = + 5 V = logic high at
the control inputs; V SS = GND = 0 V = logic low.
The maximum analog signal level is determined by V DD
and V SS . The analog voltage must not swing higher than V DD
or lower than V SS .
The example shows a 5 volt peak–to–peak signal which
ANALOG SIGNAL
+ 5 V
EXTERNAL
0–TO–5 V DIGITAL
CMOS
CONTROL SIGNALS
DIGITAL
CIRCUITRY
MOTOROLA CMOS LOGIC DATA
APPLICATIONS INFORMATION
+ 5 V
V DD
5 V p–p
SWITCH
IN
MC14066B
Figure A. Application Example
V DD
D X
SWITCH
IN
D X
V SS
Figure B. External Germanium or Schottky Clipping Diodes
allows no margin at either peak. If voltage transients above
V DD and/or below V SS are anticipated on the analog chan-
nels, external diodes (D x ) are recommended as shown in
Figure B. These diodes should be small signal types able to
absorb the maximum anticipated current surges during
clipping.
The absolute maximum potential difference between V DD
and V SS is 18.0 volts. Most parameters are specified up to
15 volts which is the recommended maximum difference
between V DD and V SS .
V SS
5 V p–p
SWITCH
OUT
ANALOG SIGNAL
V DD
D X
SWITCH
OUT
D X
V SS
+ 5.0 V
+ 2.5 V
GND
MC14066B
6–149
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