74LVQ138SCX Fairchild Semiconductor, 74LVQ138SCX Datasheet - Page 2

• Manufacturer Part Number: 74LVQ138SCX
• Description: DECODER/DEMUX 1-OF-8 LV 16SOIC
• Manufacturer: Fairchild Semiconductor
• Series: 74LVQr
• Type: Decoder/Demultiplexerr

Specifications of 74LVQ138SCX

• Circuit: 1 x 3:8
• Independent Circuits: 1
• Current - Output High, Low: 12mA, 12mA
• Voltage Supply Source: Single Supply
• Voltage - Supply: 2 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Functional Description
The LVQ138 high-speed 1-of-8 decoder/demultiplexer
accepts three binary weighted inputs (A
when enabled, provides eight mutually exclusive active-
LOW outputs (O
inputs, two active-LOW (E
All outputs will be HIGH unless E
is HIGH. This multiple enable function allows easy parallel
expansion of the device to a 1-of-32 (5 lines to 32 lines)
decoder with just four LVQ138 devices and one inverter
(see Figure 1). The LVQ138 can be used as an 8-output
demultiplexer by using one of the active LOW Enable
inputs as the data input and the other Enable inputs as
strobes. The Enable inputs which are not used must be
permanently tied to their appropriate active-HIGH or active-
LOW state.
Truth Table
H
L
X
E
H X
X H X
X
L
L
L
L
L
L
L
L
LOW Voltage Level
HIGH Voltage Level
Immaterial
1
E
X
L
L
L
L
L
L
L
L
2
E
Inputs
X
H
H
H
H
H
H
H
H
L
3
A
X
X
X
H
H
H
H
L
L
L
L
0
0
–O
A
X
X
X
H
H
H
H
L
L
L
L
1
7
). The LVQ138 features three Enable
A
X
X
X
H
H
H
H
L
L
L
L
2
1
O
H
H
H
H
H
H
H
H
H
H
, E
L
0
2
O
) and one active-HIGH (E
H
H
H
H
H
H
H
H
H
H
L
1
1
and E
O
H
H
H
H
H
H
H
H
H
H
L
2
Outputs
FIGURE 1. Expansion to 1-of-32 Decoding
O
H
H
H
H
H
H
H
H
H
H
L
2
3
are LOW and E
0
O
, A
H
H
H
H
H
H
H
H
H
H
L
4
1
O
, A
H
H
H
H
H
H
H
H
H
H
L
5
2
O
H
H
H
H
H
H
H
H
H
H
) and,
L
6
O
H
H
H
H
H
H
H
H
H
H
3
L
).
7
3
2
Logic Diagram
Please note that this diagram is provided only for the understanding of logic
operations and should not be used to estimate propagation delays.