MC74VHT4051 Datasheet, PDF (9/12 Pages) Motorola, Inc – Analog Multiplexer Demultiplexer

MC74VHCT4051
VIS
RL
16
VOS
fin
ON
0.1µF
OFF
RL
6
8
RL
CL* ^RL
CL*
*Includes all probe and jig capacitance
Figure 12. Crosstalk Between Any Two
Switches, Test Set–Up
VIS
0.1µF
fin
VCC
16
ON
VOS
RL
CL*
TO
DISTORTION
METER
6
8
*Includes all probe and jig capacitance
Figure 14a. Total Harmonic Distortion, Test Set–Up
VCC
ANALOG I/O
VCC
A
16
ON/OFF
OFF/ON
COMMON O/I
NC
6
VCC
8
11
CHANNEL SELECT
Figure 13. Power Dissipation Capacitance,
Test Set–Up
0
– 10
FUNDAMENTAL FREQUENCY
– 20
– 30
– 40
– 50
DEVICE
– 60
SOURCE
– 70
– 80
– 90
– 100
1.0
2.0
3.125
FREQUENCY (kHz)
Figure 14b. Plot, Harmonic Distortion
APPLICATIONS INFORMATION
The Channel Select and Enable control pins should be at
VCC or GND logic levels. VCC being recognized as a logic
high and GND being recognized as a logic low. In this exam-
ple:
VCC = +5V = logic high
GND = 0V = logic low
The maximum analog voltage swing is determined by the
supply voltage VCC. The positive peak analog voltage should
not exceed VCC. Similarly, the negative peak analog voltage
should not go below GND. In this example, the difference
between VCC and GND is five volts. Therefore, using the
configuration of Figure 15, a maximum analog signal of five
volts peak–to–peak can be controlled. Unused analog
inputs/outputs may be left floating (i.e., not connected). How-
ever, tying unused analog inputs and outputs to VCC or GND
through a low value resistor helps minimize crosstalk and
feedthrough noise that may be picked up by an unused
switch.
Although used here, balanced supplies are not a require-
ment. The only constraints on the power supplies are that:
VCC – GND = 2 to 6 volts
When voltage transients above VCC and/or below GND
are anticipated on the analog channels, external Germanium
or Schottky diodes (Dx) are recommended as shown in Fig-
ure 16. These diodes should be able to absorb the maximum
anticipated current surges during clipping.
VHC Data – Advanced CMOS Logic
9
DL203 — Rev 2
MOTOROLA