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SN74LS245 Octal Bus Transceiver
The SN74LS245 is an Octal Bus Transmitter/Receiver designed for 8-line asynchronous 2-way data communication between data buses. Direction Input (DR) controls transmission of Data from bus A to bus B or bus B to bus A depending upon its logic level. The Enable input (E) can be used to isolate the buses.
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Hysteresis Inputs toImprove Noise Immunity 2-Way Asynchronous Data Bus Communication Input Diodes Limit High-Speed Termination Effects ESD > 3500 Volts
LOGIC AND CONNECTION DIAGRAMS DIP (TOP VIEW)
VCC 20 E 19 B1 18 B2 17 B3 16 B4 15 B5 14 B6 13 B7 12 B8 11

LOW POWER SCHOTTKY

20 1

1 DIR

2 A1

3 A2

4 A3

5 A4

6 A5

7 A6

8 A7

9 A8

10 GND

PLASTIC N SUFFIX CASE 738

TRUTH TABLE
INPUTSOUTPUT E L L H DIR L H X Bus B Data to Bus A Bus A Data to Bus B Isolation
20 1

H = HIGH Voltage Level L = LOW Voltage Level X = Immaterial

SOIC DW SUFFIX CASE 751D

GUARANTEED OPERATING RANGES
Symbol VCC TA IOH Parameter Supply Voltage Operating Ambient Temperature Range Output Current – High Min 4.75 0 Typ 5.0 25 Max 5.25 70 – 3.0 – 15 IOL Output Current – Low 24 Unit V °C mA mA mADevice SN74LS245N SN74LS245DW Package 16 Pin DIP 16 Pin Shipping 1440 Units/Box 2500/Tape & Reel

ORDERING INFORMATION

© Semiconductor Components Industries, LLC, 1999

1

December, 1999 – Rev. 6

Publication Order Number: SN74LS245/D

SN74LS245
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)
Limits Symbol VIH VIL VT+–VT– VIK VO OH Parameter InputHIGH Voltage Input LOW Voltage Hysteresis Input Clamp Diode Voltage 2.4 Output HIGH Voltage 2.0 0.25 VO OL IOZH IOZL Output LOW Voltage 0.35 Output Off Current HIGH Output Off Current LOW A or B, DR or E IIH Input HIGH C I t Current t DR or E A or B IIL IOS Input LOW Current Output Short Circuit Current (Note 1) Power Supply Current Total, Output HIGH ICC Total, Output LOW Total at HIGH Z – 40 0.520 – 200 20 0.1 0.1 – 0.2 – 225 70 90 95 mA A VCC = MAX V µA µA µA mA mA mA mA IOL = 24 mA 0.4 V V 0.2 0.4 – 0.65 3.4 – 1.5 Min 2.0 0.8 Typ Max Unit V V V V V Test Conditions Guaranteed Input HIGH Voltage for All Inputs Guaranteed Input LOW Voltage for All Inputs VCC = MIN VCC = MIN, IIN = – 18 mA VCC = MIN, IOH = – 3.0 mA VCC = MIN, IOH = MAX IOL = 12 mA VCC = VCC MIN, VIN = VIL or VIH per TruthTable

VCC = MAX, VOUT = 2.7 V VCC = MAX, VOUT = 0.4 V VCC = MAX, VIN = 2.7 V VCC = MAX, VIN = 7.0 V VCC = MAX, VIN = 5.5 V VCC = MAX, VIN = 0.4 V VCC = MAX

Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.

AC CHARACTERISTICS (TA = 25°C, VCC = 5.0 V, TRISE / TFALL ≤ 6.0 ns)
Limits Symbol tPLH tPHL tPZH tPZL tPLZ tPHZ Parameter Propagation Delay,Data to Output Output Enable Time to HIGH Level Output Enable Time to LOW Level Output Disable Time from LOW Level Output Disable Time from HIGH Level Min Typ 8.0 8.0 25 27 15 15 Max 12 12 40 40 25 25 Unit ns ns ns ns ns CL = 5.0 pF, RL = 667 Ω CL = 45 pF, F, RL = 667 Ω Test Conditions

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2

SN74LS245
PACKAGE DIMENSIONS

N SUFFIX PLASTIC PACKAGE CASE 738–03 ISSUE E
–A–
2011 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 4. DIMENSION B DOES NOT INCLUDE MOLD FLASH. INCHES MIN MAX 1.010 1.070 0.240 0.260 0.150 0.180 0.015 0.022 0.050 BSC 0.050 0.070 0.100 BSC 0.008 0.015 0.110 0.140 0.300 BSC 0_ 15 _ 0.020 0.040 MILLIMETERS MIN MAX 25.66 27.17 6.10 6.60 3.81 4.570.39 0.55 1.27 BSC 1.27 1.77 2.54 BSC 0.21 0.38 2.80 3.55 7.62 BSC 0_ 15_ 0.51 1.01

B
1 10

C

L

–T–
SEATING PLANE

K M E G F D
20 PL

N J 0.25 (0.010)
M 20 PL

0.25 (0.010) T A
M

M

T B

M

DIM A B C D E F G J K L M N

D SUFFIX PLASTIC SOIC PACKAGE CASE 751D–05 ISSUE F

D

A
11 X 45 _

q
NOTES: 1. DIMENSIONS ARE IN MILLIMETERS. 2. INTERPRET DIMENSIONS AND...
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