急，谁能提供给我74ls245的功能说明和引脚图，谢谢了

哪一个才是74LS245的引脚图？~

第一种按引脚顺序排列，并且列出内部功能。
第二种按功能分块排列。
在你画原理图的时候，如果有很多74系列的逻辑芯片，用第二种画法，花完之后整个图会好看很多。

74HC245应该没有国产的，都是德州，飞利浦，仙童之类的国外品牌，只有英文资料
www.alldatasheet.co.kr

74ls245引脚图与用法
74LS245引脚图
74LS245是我们常用的芯片，用来驱动led或者其他的设备,用法很简单如上图,这里简单的给出一些资料，他是8路同相三态双向总线收发器，可双向传输数据。
74LS245还具有双向三态功能，既可以输出，也可以输入数据。
当8051单片机的P0口总线负载达到或超过P0最大负载能力时，必须接入74LS245等总线驱动器。
当片选端/CE低电平有效时，DIR=“0”，信号由 B 向 A 传输；（接收）
*DIR=“1”，信号由 A 向 B 传输；（发送）当/CE为高电平时，A、B均为高阻态。

74LS245是我们常用的芯片，用来驱动led或者其他的设备，它是8路同相三态双向总线收发器，可双向传输数据。
　　*74LS245还具有双向三态功能，既可以输出，也可以输入数据。
　　*当8051单片机的P0口总线负载达到或超过P0最大负载能力时，必须接入74LS245等总线驱动器。
　　*当片选端/CE低电平有效时，DIR=“0”，信号由 B 向 A 传输；（接收）
　　*DIR=“1”，信号由 A 向 B 传输；（发送）当/CE为高电平时，A、B均为高阻态。
　　由于P2口始终输出地址的高8位，接口时74LS245的三态控制端/1G和/2G接地，P2口与驱动器输入线对应相连。
P0口与74LS245输入端相连,/E端接地，保证数据现畅通。8051的/RD和/PSEN相与后接DIR，使得/RD或/PSEN有效时，74LS245输入（P0.i←Di），其它时间处于输出（P0.i→Di）。
不好意思，图片太大弄不上

我的资料是PDF的，图贴不上去，文字部分如下

TL/F/6413
54LS245/DM54LS245/DM74LS245 TRI-STATE Octal Bus Transceiver
June 1989
54LS245/DM54LS245/DM74LS245
TRI-STATEÉ Octal Bus Transceiver
General Description
These octal bus transceivers are designed for asynchronous
two-way communication between data buses. The
control function implementation minimizes external timing
requirements.
The device allows data transmission from the A bus to the B
bus or from the B bus to the A bus depending upon the logic
level at the direction control (DIR) input. The enable input
(G) can be used to disable the device so that the buses are
effectively isolated.
Features
Y Bi-Directional bus transceiver in a high-density 20-pin
package
Y TRI-STATE outputs drive bus lines directly
Y PNP inputs reduce DC loading on bus lines
Y Hysteresis at bus inputs improve noise margins
Y Typical propagation delay times, port-to-port 8 ns
Y Typical enable/disable times 17 ns
Y IOL (sink current)
54LS 12 mA
74LS 24 mA
Y IOH (source current)
54LS b12 mA
74LS b15 mA
Y Alternate Military/Aerospace device (54LS245) is available.
Contact a National Semiconductor Sales Office/
Distributor for specifications.
Connection Diagram
Dual-In-Line Package
TL/F/6413±1
Order Number 54LS245DMQB, 54LS245FMQB, 54LS245LMQB,
DM54LS245J, DM54LS245W, DM74LS245WM or DM74LS245N
See NS Package Number E20A, J20A, M20B, N20A or W20A
Function Table
Enable
Direction
Operation
G
Control
DIR
L L B data to A bus
L H A data to B bus
H X Isolation
H e High Level, L e Low Level, X e Irrelevant
TRI-STATEÉ is a registered trademark of National Semiconductor Corporation.
C1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.
Absolute Maximum Ratings (Note)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage 7V
Input Voltage
DIR or G 7V
A or B 5.5V
Operating Free Air Temperature Range
DM54LS and 54LS b55§C to a125§C
DM74LS 0§C to a70§C
Storage Temperature Range b65§C to a150§C
Note: The ``Absolute Maximum Ratings'' are those values
beyond which the safety of the device cannot be guaranteed.
The device should not be operated at these limits. The
parametric values defined in the ``Electrical Characteristics''
table are not guaranteed at the absolute maximum ratings.
The ``Recommended Operating Conditions'' table will define
the conditions for actual device operation.
Recommended Operating Conditions
Symbol Parameter
DM54LS245 DM74LS245
Units
Min Nom Max Min Nom Max
VCC Supply Voltage 4.5 5 5.5 4.75 5 5.25 V
VIH High Level Input Voltage 2 2 V
VIL Low Level Input Voltage 0.7 0.8 V
IOH High Level Output Current b12 b15 mA
IOL Low Level Output Current 12 24 mA
TA Free Air Operating Temperature b55 125 0 70 §C
Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted)
Symbol Parameter Conditions Min
Typ
Max Units
(Note 1)
VI Input Clamp Voltage VCC e Min, IIe b18 mA b1.5 V
HYS Hysteresis (VTa b VTb) VCC e Min 0.2 0.4 V
VOH High Level Output Voltage VCC e Min, VIH e Min DM74
2.7
VIL e Max, IOHe b1 mA
VCC e Min, VIL e Min DM54/DM74
2.4 3.4 V
VIL e Max, IOHe b3 mA
VCC e Min, VIH e Min DM54/DM74
2
VIL e 0.5V, IOH e Max
VOL Low Level Output Voltage VCC e Min IOL e 12 mA DM74 0.4
VIL e Max
IOL e Max DM54 0.4 V
VIH e Min
DM74 0.5
IOZH Off-State Output Current, VCC e Max VO e 2.7V
20 mA
High Level Voltage Applied VIL e Max
IOZL Off-State Output Current,
VIH e Min
VO e 0.4V
b200 mA
Low Level Voltage Applied
II Input Current at Maximum VCC e Max A or B VI e 5.5V 0.1
mA
Input Voltage
DIR or G VI e 7V 0.1
IIH High Level Input Current VCC e Max, VI e 2.7V 20 mA
IIL Low Level Input Current VCC e Max, VI e 0.4V b0.2 mA
IOS Short Circuit Output Current VCC e Max (Note 2) b40 b225 mA
ICC Supply Current Outputs High VCC e Max 48 70
Outputs Low 62 90 mA
Outputs at Hi-Z 64 95
Note 1: All typicals are at VCC e 5V, TA e 25§C.
Note 2: Not more than one output should be shorted at a time, not to exceed one second duration
2
Switching Characteristics VCC e 5V, TA e 25§C (See Section 1 for Test Waveforms and Output Load)
DM54/74
Symbol Parameter Conditions LS245 Units
Min Max
tPLH Propagation Delay Time, Low-to-High-Level Output 12 ns
tPHL Propagation Delay Time, High-to-Low-Level Output CL e 45 pF 12 ns
tPZL Output Enable Time to Low Level
RL e 667X 40 ns
tPZH Output Enable Time to High Level 40 ns
tPLZ Output Disable Time from Low Level CL e 5 pF 25 ns
tPHZ Output Disable Time from High Level
RL e 667X 25 ns
tPLH Propagation Delay Time, Low-to-High-Level Output 16 ns
tPHL Propagation Delay Time, High-to-Low-Level Output CL e 150 pF 17 ns
tPZL Output Enable Time to Low Level
RL e 667X 45 ns
tPZH Output Enable Time to High Level 45 ns
3
Physical Dimensions inches (millimeters)
Ceramic Leadless Chip Carrier Package (E)
Order Number 54LS245LMQB
NS Package Number E20A
20-Lead Ceramic Dual-In-Line Package (J)
Order Number 54LS245DMQB or DM54LS245J
NS Package Number J20A
4
Physical Dimensions inches (millimeters) (Continued)
20-Lead Small Outline Molded Package (M)
Order Number DM74LS245WM
NS Package Number M20B
20-Lead Molded Dual-In-Line Package (N)
Order Number DM74LS245N
NS Package Number N20A
5
54LS245/DM54LS245/DM74LS245 TRI-STATE Octal Bus Transceiver
Physical Dimensions inches (millimeters) (Continued)
20-Lead Ceramic Flat Package (W)
Order Number 54LS245FMQB or DM54LS245W
NS Package Number W20A
LIFE SUPPORT POLICY
NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or 2. A critical component is any component of a life
systems which, (a) are intended for surgical implant support device or system whose failure to perform can
into the body, or (b) support or sustain life, and whose be reasonably expected to cause the failure of the life
failure to perform, when properly used in accordance support device or system, or to affect its safety or
with instructions for use provided in the labeling, can effectiveness.
be reasonably expected to result in a significant injury
to the user.
National Semiconductor National Semiconductor National Semiconductor National Semiconductor
Corporation Europe Hong Kong Ltd. Japan Ltd.
1111 West Bardin Road Fax: (a49) 0-180-530 85 86 13th Floor, Straight Block, Tel: 81-043-299-2309
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.

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伊宁市17373009315： 急,谁能提供给我74ls245的功能说明和引脚图,谢谢了 - ？
台房山香： 74ls245引脚图与用法74LS245引脚图 74LS245是我们常用的芯片,用来驱动led或者其他的设备,用法很简单如上图,这里简单的给出一些资料,他是8路同相三态双向总线收发器,可双向传输数据. 74LS245还具有双向三态功能,既可以输...

伊宁市17373009315： 谁用Verilog帮我写一个74LS245的程序 - ？
台房山香： module \74ls245 ( A, B, C, D, RBIN, BIN, LTIN, RBON, OA, OB, OC, OD, OE, OF, OG); input A; input B; input C; input D; input RBIN; input BIN; input LTIN; output RBON; output OA; output OB; output OC; output OD; output OE; output OF; output OG; ...

伊宁市17373009315： 74LS245怎么驱动数码管 与单片机P0接口 是怎么接的 - ？
台房山香： 74LS245是8位双向数据总线收/发器(缓冲器),带高阻输出,DI(1#)决定数据的方向,G(19#)决定输出状态,驱动数码管可以这么做:2#—9#接P0,18#—11#(不可反序)接数码管.1#接VCC(高电平),19#接GND(低电平),这是驱动一个数码管的接法.如果要驱动多个数码管,19#接扫描信号,可以采用74LS138的输出端.

伊宁市17373009315： 74LS245工作电流 - ？
台房山香： 只要不超过7805的额定电流值就可以了 如果正常的话加一个散热片就可以啊

伊宁市17373009315： 求使用AT89C51单片机和74LS245来实现数字钟的C语言代码,只要能显示时分秒就行.K3开关,K1是选择键,K2是 - ？
台房山香： 如只编程序,可以.如做实物:AT89C51单片机功能强大,不用74245,可用巡回显示法,但应加一个DS1302之类的时钟电路,否则时间不会太准,甚至用不了,还有就是一断电就要重调时间,你受得了吗.

伊宁市17373009315： 关于74LS系列的245芯片？
台房山香： 若我的记忆没错的话,74LS 系列有两种产品 (现可能多过2种).一是普通的 5v,乃另一种是用CMOS 的芯片用 3.3v, 具体是看 74 xx 那两个xx字.CMOS 好像是用 74C xxx 表示.

伊宁市17373009315： 求数字时钟程序,是用51单片机做的,我们实验室里能提供六个数码管,一个74ls245,一个74ls138译码器,只需？
台房山香： 74ls138三八译码器,A\B\C分别接P1.0\P1.1\P1.2,Y0~Y7分别接0~7号数码管(共阴极),输出格式是: 23-59-59,你只用6个数码管,就把中间的两个横杠去掉就行了,代码修改一下.(不仅是代码中用于显示-的部分,还有数码管的控制字,...

伊宁市17373009315： 用STC89c51通过74LS245驱动数码管,数码管亮度很低 - ？
台房山香： 不是电阻太小了,而是大了,换成51Ω或者33Ω试试.

伊宁市17373009315： 74LS138与74 LS245的区别【悬赏】 - ？
台房山香： 74LS138和74LS245的功能完全不同,不是参数差异问题.前者是三——八译码器,后者是三态输出的总线收发器.

伊宁市17373009315： 74ls245的作用,能否把提供电平转换,3.3V转5V? - ？
台房山香： 74LS245 有电流增大作用,一般用于总线驱动,但无电平转换作用.