MC74HC4316A
http://onsemi.com
8
APPLICATIONS INFORMATION
0
-10
-20
-30
-40
-50
- 100
1.0 2.0
FREQUENCY (kHz)
dBm
-60
-70
-80
-90
FUNDAMENTAL FREQUENCY
DEVICE
SOURCE
Figure 16. Plot, Harmonic Distortion
3.0
The Enable and Control pins should be at V
CC
or GND
logic levels, V
CC
being recognized as logic high and GND
being recognized as a logic low. Unused analog
inputs/outputs may be left floating (not connected).
However, it is advisable to tie unused analog inputs and
outputs to V
CC
or V
EE
through a low value resistor. This
minimizes crosstalk and feedthrough noise that may be
picked up by the unused I/O pins.
The maximum analog voltage swings are determined by
the supply voltages V
CC
and V
EE
. The positive peak analog
voltage should not exceed V
CC
. Similarly, the negative peak
analog voltage should not go below V
EE
. In the example
below, the difference between V
CC
and V
EE
is 12 V.
Therefore, using the configuration in Figure 17, a maximum
analog signal of twelve volts peak−to−peak can be
controlled.
When voltage transients above V
CC
and/or below V
EE
are
anticipated on the analog channels, external diodes (Dx) are
recommended as shown in Figure 18. These diodes should
be small signal, fast turn−on types able to absorb the
maximum anticipated current surges during clipping. An
alternate method would be to replace the Dx diodes with
MOSORBs (MOSORBt is an acronym for high current
surge protectors). MOSORBs are fast turn−on devices
ideally suited for precise dc protection with no inherent wear
out mechanism.
ANALOG O/I
ON
16
V
CC
= 6 V
ANALOG I/O
+ 6 V
-6 V
+ 6 V
-6 V
ENABLE CONTROL
INPUTS
(V
CC
OR GND)
ON
16
V
CC
D
x
D
x
V
CC
D
x
Figure 17. Figure 18. Transient Suppressor Application
8
SELECTED
CONTROL
INPUT
D
x
SELECTED
CONTROL
INPUT
+ 6 V
V
EE
-6 V
V
CC
V
EE
ENABLE CONTROL
INPUTS
(V
CC
OR GND)
V
EE
V
EE
