MC74HC4851A Datasheet, PDF (6/12 Pages) ON Semiconductor – Analog Multiplexers/Demultiplexers with Injection Current Effect Control

MC74HC4851A, MC74HC4852A
Iin
Vin2 < VSS or VCC < Vin2
Any Disabled Channel
VSS < Vin1 < VCC
Enabled Channel
RS
VCC = 5V
Vout = Vin1 ±V∆_out
Figure 9. Injection Current Coupling Specification
5V
Sensor
(8x Identical Circuitry)
6V
5V VCC
VCC
HC4051A
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
Common Out
Microcontroller
A/D – Input
Figure 10. Actual Technology
Requires 32 passive components and one extra 6V regulator
to suppress injection current into a standard HC4051 multiplexer
Sensor
(8x Identical Circuitry)
5V
VCC
HC4851A
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
Common Out
VCC
Microcontroller
A/D – Input
Figure 11. MC74HC4851A Solution
Solution by applying the HC4851A multiplexer
http://onsemi.com
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