Changhong Electric 21BM91, Руководство по обслуживанию, Страница: 44 / 58

SERVICE MANUAL
7. HEF4053BP
TRIPLE 2-CHANNEL ANALOG MULTIPLEXER/DEMULTIPLEXER
1). Description
The HEF4053 is a triple 2-channel analog multiplexer/demultiplexer with a common enable input (E).
Each multiplexer/demultiplexer has two independent inputs/outputs (Y
0
and Y
1
), a common input/output
(Z), and select inputs (Sn). Each also contains two-bidirectional analog switches, each with one side
connected to an independent input/output (Y
0
and Y
1
) and the other side connected to a common
input/output(Z).
With (E) LOW, one of the two switches is selected (low impedance ON-state) by Sn. With E HIGH, all
switches are in the high impedance OFF-state, independent of S
A
to S
C
.
V
DD
and V
SS
are the supply voltage connections for the digital control inputs (S
A
to S
C
and E).
The V
DD
to V
SS
range is 3 to 15V.The analog inputs/outputs (Y
0
, Y
1
and Z) can swing between V
DD
as a
positive limit and V
EE
as a negative limit. V
DD
-V
EE
may not exceed 15 V.
For operation as a digital multiplexer/demultiplexer, V
EE
is connected to V
SS
(typically ground).
2). Block Diagram
Fig. 22 Functional Diagram
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