參數(shù)資料
型號: DM74LS257BM
廠商: FAIRCHILD SEMICONDUCTOR CORP
元件分類: 通用總線功能
英文描述: 3-STATE Quad 2-Data Selectors/Multiplexers
中文描述: LS SERIES, QUAD 2 LINE TO 1 LINE MULTIPLEXER, TRUE OUTPUT, PDSO16
封裝: 0.150 INCH, MS-012, SOIC-16
文件頁數(shù): 1/5頁
文件大?。?/td> 56K
代理商: DM74LS257BM
1999 Fairchild Semiconductor Corporation
DS006417
www.fairchildsemi.com
June 1989
Revised November 1999
D
DM74LS257B
3-STATE Quad 2-Data Selectors/Multiplexers
General Description
These Schottky-clamped high-performance multiplexers
feature 3-STATE outputs that can interface directly with
data lines of bus-organized systems. With all but one of the
common outputs disabled (at a high impedance state), the
low impedance of the single enabled output will drive the
bus line to a HIGH or LOW logic level. To minimize the pos-
sibility that two outputs will attempt to take a common bus
to opposite logic levels, the output enable circuitry is
designed such that the output disable times are shorter
than the output enable times.
This 3-STATE output feature means that n-bit (paralleled)
data selectors with up to 258 sources can be implemented
for data buses. It also permits the use of standard TTL reg-
isters for data retention throughout the system.
Features
I
3-STATE versions LS157 and LS158 with same pinouts
I
Schottky-clamped for significant improvement in A-C
performance
I
Provides bus interface from multiple sources in
high-performance systems
I
Average propagation delay from data input 12 ns
I
Typical power dissipation:
50 mW
Ordering Code:
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
Function Table
H
=
HIGH Level
L
=
LOW Level
X
=
Don’t Care
Z
=
High Impedance (off)
Logic Diagram
Order Number
DM74LS257BM
DM74LS257BN
Package Number
M16A
N16E
Package Description
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Inputs
Output Y
Output
Control
H
L
L
L
L
Select
A
B
LS257
X
L
L
H
H
X
L
H
X
X
X
X
X
L
H
Z
L
H
L
H
相關PDF資料
PDF描述
DM74LS257B 3-STATE Quad 2-Data Selectors/Multiplexers(三態(tài)輸出的四2數(shù)據(jù)選擇器)
DM74LS257BN 3-STATE Quad 2-Data Selectors/Multiplexers
DM74LS257 3-STATE Quad 2-Data Selectors/Multiplexers
DM74LS257BMX 2-Input Digital Multiplexer
DM74LS259WM 8-Bit Addressable Latches
相關代理商/技術參數(shù)
參數(shù)描述
DM74LS257BMX 功能描述:編碼器、解碼器、復用器和解復用器 3-STATE Data Sel/Mul 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
DM74LS257BN 功能描述:編碼器、解碼器、復用器和解復用器 3-STATE Data Sel/Mul 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
DM74LS257N 制造商:Texas Instruments 功能描述: 制造商:National Semiconductor Corporation 功能描述:LOGIC MUX, QUAD, 2-INPUT, LS-TTL, 16 Pin, Plastic, DIP
DM74LS258BM 制造商:Rochester Electronics LLC 功能描述:- Bulk
DM74LS259 WAF 制造商:Fairchild Semiconductor Corporation 功能描述: