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DM74LS243N

Part # DM74LS243N
Description IC TXRX BUS QUAD 4LINE 14-DIP
Category IC
Availability In Stock
Qty 7
Qty Price
1 + $0.09805
Manufacturer Available Qty
National Semiconductor Corp
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National Semiconductor Corp
Date Code: 9124
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Technical Document


DISCLAIMER: The information provided herein is solely for informational purposes. Customers must be aware of the suitability of this product for their application, and consider that variable factors such as Manufacturer, Product Category, Date Codes, Pictures and Descriptions may differ from available inventory.

© 2000 Fairchild Semiconductor Corporation DS006412 www.fairchildsemi.com
August 1986
Revised January 2000
DM74LS243 Quadruple Bus Transceiver
DM74LS243
Quadruple Bus Transceiver
General Description
This four data line transceiver is designed for asynchro-
nous two-way communications between data buses. It can
be used to drive terminated lines down to 133.
Features
Two-way asynchronous communication between data
buses
PNP inputs reduce DC loading on bus line
Hysteresis at data inputs improves noise margin
Ordering Code:
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram Function Table
I = Input
O = Output
H = HIGH Logic Level
L = LOW Logic Level
Note 1: Possibly destructive oscillation may occur if the transceivers are
enabled in both directions at once.
Order Number Package Number Package Description
DM74LS243M M14A 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150 Narrow
DM74LS243N N14A 14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Control Data Port
Inputs Status
G
AB GBA A B
HHOI
L H (Note 1) (Note 1)
H L ISOLATED
LLIO
www.fairchildsemi.com 2
DM74LS243
Absolute Maximum Ratings(Note 2)
Note 2: 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 tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
Recommended Operating Conditions
Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 3: All typicals are at V
CC
= 5V, T
A
= 25°C.
Note 4: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Supply Voltage 7V
Input Voltage
Any G 7V
A or B 5.5V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range 65°C to +150°C
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.75 5 5.25 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current 15 mA
I
OL
LOW Level Output Current 24 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min
Typ
Max Units
(Note 3)
V
I
Input Clamp Voltage V
CC
= Min, I
I
= 18 mA 1.5 V
HYS Hysteresis (V
T+
V
T
)V
CC
= Min 0.2 0.4 V
(Data Inputs Only)
V
OH
HIGH Level Output Voltage V
CC
= Min, V
IH
= Min 2.7
V
IL
= Max, I
OH
= 1 mA
V
CC
= Min, V
IH
= Min 2.4 3.4 V
V
IL
= Max, I
OH
= 3 mA
V
CC
= Min, V
IH
= Min 2
V
IL
= 0.5V, I
OH
= Max
V
OL
LOW Level Output Voltage V
CC
= Min I
OL
= 12 mA 0.4
V
IL
= Max I
OL
= Max V
V
IH
= Min 0.5
I
OZH
Off-State Output Current, V
CC
= Max V
O
= 2.7V 40 µA
HIGH Level Voltage Applied V
IL
= Max
I
OZL
Off-State Output Current, V
IH
= Min V
O
= 0.4V 200 µA
LOW Level Voltage Applied
I
I
Input Current at Maximum V
CC
= Max V
I
= 5.5V A or B 0.1 mA
Input Voltage V
I
= 7V Any G 0.1 mA
I
IH
HIGH Level Input Current V
CC
= Max, V
I
= 2.7V 20 µA
I
IL
LOW Level Input Current V
CC
= Max, V
I
= 0.4V 0.2 mA
I
OS
Short Circuit Output Current V
CC
= Max (Note 4) 40 225 mA
I
CC
Supply Current V
CC
= Max Outputs HIGH 22 38
Outputs Outputs LOW 29 50 mA
OPEN Outputs Disabled 32 54
3 www.fairchildsemi.com
DM74LS243
Switching Characteristics
at V
CC
= 5V, T
A
= 25°C
Symbol Parameter Conditions Min Max Units
t
PLH
Propagation Delay Time C
L
= 45 pF
18 ns
LOW-to-HIGH Level Output R
L
= 667
t
PHL
Propagation Delay Time C
L
= 45 pF
18 ns
HIGH-to-LOW Level Output R
L
= 667
t
PZL
Output Enable Time C
L
= 45 pF
30 ns
to LOW Level R
L
= 667
t
PZH
Output Enable Time C
L
= 45 pF
23 ns
to HIGH Level R
L
= 667
t
PLZ
Output Disable Time C
L
= 5 pF
25 ns
from LOW Level R
L
= 667
t
PHZ
Output Disable Time C
L
= 5 pF
18 ns
from HIGH Level R
L
= 667
t
PLH
Propagation Delay Time C
L
= 150 pF
21 ns
LOW-to-HIGH Level Output R
L
= 667
t
PHL
Propagation Delay Time C
L
= 150 pF
22 ns
HIGH-to-LOW Level Output R
L
= 667
t
PZL
Output Enable Time C
L
= 150 pF
33 ns
to LOW Level R
L
= 667
t
PZH
Output Enable Time C
L
= 150 pF
26 ns
to HIGH Level R
L
= 667
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