Datasheet

SN74HC4851-Q1
8-CHANNEL ANALOG MULTIPLEXER/DEMUL TIPLEXER
WITH INJECTION-CURRENT EFFECT CONTROL
SCLS554C
−
JANUARY 2004
−
REVISED SEPTEMBER 2012
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
8
APPLICATION INFORMA TION
5 V
V
CC
Sensor
’HC4851
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
V
CC
Microcontroller
(8× Identical
Circuitry)
Channel 6
Channel 7
Channel 8
Common Out
A/D − Input
Figure 3. Solution by Applying the ’HC4851 Multiplexer
Disabled Analog Multiplex Input
V
IN
> V
CC
+ 0.7 V
Gate = V
CC
(Disabled)
Common Analog Output
V
out
> V
CC
P+ P+
+
+
+
N − Substrate (on V
CC
potential)
Figure 4. Diagram of Bipolar Coupling Mechanism
(Appears if V
IN
Exceeds V
CC
, Driving Injection Current Into the Substrate)