參數(shù)資料
型號: MC74ACT257MEL
廠商: ON SEMICONDUCTOR
元件分類: 通用總線功能
英文描述: Quad 2−Input Multiplexer with 3−State Outputs
中文描述: ACT SERIES, QUAD 2 LINE TO 1 LINE MULTIPLEXER, TRUE OUTPUT, PDSO16
封裝: PLASTIC, EIAJ-16
文件頁數(shù): 2/12頁
文件大?。?/td> 191K
代理商: MC74ACT257MEL
MC74AC257, MC74ACT257
http://onsemi.com
2
PIN NAME
PIN
FUNCTION
S
Common Data Select Input
OE
3
State Output Enable Input
I
0a
I
0d
Data Inputs from Source 0
I
1a
I
1d
Data Inputs from Source 1
Z
a
Z
d
3
State Multiplexer Outputs
TRUTH TABLE
Output
Enable
Select
Input
Data
Inputs
Outputs
OE
S
I
0
I
1
Z
H
L
L
L
L
X
H
H
L
L
X
X
X
L
H
X
L
H
X
X
Z
L
H
L
H
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance
Figure 2. Logic Symbol
S
OE I
0a
I
1a
I
0b
I
1b
Z
b
I
0c
I
1c
I
0d
I
1d
Z
a
Z
c
Z
d
FUNCTIONAL DESCRIPTION
The MC74AC257/74ACT257 is a quad 2
input
multiplexer with 3
state outputs. It selects four bits of data
from two sources under control of a Common Data Select
input. When the Select input is LOW, the I
0x
inputs are
selected and when Select is HIGH, the I
1x
inputs are
selected. The data on the selected inputs appears at the
outputs in true (noninverted) form. The device is the logic
implementation of a 4
pole, 2
position switch where the
position of the switch is determined by the logic levels
supplied to the Select input. The logic equations for the
outputs are shown below:
Z
a
= OE
(I
1a
S+I
0a
S)
Z
b
= OE
(I
1b
S+I
0b
S)
Z
c
= OE
(I
1c
S+I
0c
S)
Z
d
= OE
(I
1d
S+I
0d
S)
When the Output Enable input (OE) is HIGH, the outputs
are forced to a high impedance state. If the outputs are tied
together, all but one device must be in the high impedance
state to avoid high currents that would exceed the maximum
ratings. Designers should ensure the Output Enable signals
to 3
state devices whose outputs are tied together are
designed so there is no overlap.
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相關代理商/技術參數(shù)
參數(shù)描述
MC74ACT257MELG 功能描述:編碼器、解碼器、復用器和解復用器 5V Dual 4-Input w/3-State Out RoHS:否 制造商:Micrel 產(chǎn)品:Multiplexers 邏輯系列:CMOS 位數(shù): 線路數(shù)量(輸入/輸出):2 / 12 傳播延遲時間:350 ps, 400 ps 電源電壓-最大:2.625 V, 3.6 V 電源電壓-最小:2.375 V, 3 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-44 封裝:Tray
MC74ACT257N 功能描述:編碼器、解碼器、復用器和解復用器 5V Dual 4-Input RoHS:否 制造商:Micrel 產(chǎn)品:Multiplexers 邏輯系列:CMOS 位數(shù): 線路數(shù)量(輸入/輸出):2 / 12 傳播延遲時間:350 ps, 400 ps 電源電壓-最大:2.625 V, 3.6 V 電源電壓-最小:2.375 V, 3 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-44 封裝:Tray
MC74ACT257NG 功能描述:編碼器、解碼器、復用器和解復用器 5V Dual 4-Input w/3-State Out RoHS:否 制造商:Micrel 產(chǎn)品:Multiplexers 邏輯系列:CMOS 位數(shù): 線路數(shù)量(輸入/輸出):2 / 12 傳播延遲時間:350 ps, 400 ps 電源電壓-最大:2.625 V, 3.6 V 電源電壓-最小:2.375 V, 3 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-44 封裝:Tray
MC74ACT258D 制造商:Rochester Electronics LLC 功能描述:- Bulk
MC74ACT258N 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:QUAD 2-INPUT MULTIPLEXER WITH 3-STATE OUTPUTS