Texas Instruments SN74AHC245DBLE, SN74AHC245DBR, SN74AHC245DGVR, SN74AHC245DW, SN74AHC245DWR Datasheet
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OPERATION
SN54AHC245, SN74AHC245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCLS230G – OCTOBER 1995 – REVISED JANUARY 2000
D
EPIC
(Enhanced-Performance Implanted
CMOS) Process
D
Operating Range 2-V to 5.5-V V
D
Latch-Up Performance Exceeds 250 mA Per
CC
JESD 17
D
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), Thin Very Small-Outline (DGV), Thin
Shrink Small-Outline (PW), and Ceramic
Flat (W) Packages, Ceramic Chip Carriers
(FK), and Standard Plastic (N) and Ceramic
(J) DIPs
description
The ’AHC245 octal bus transceivers are designed
for asynchronous two-way communication
between data buses. The control-function
implementation minimizes external timing
requirements.
These devices allow data transmission from the A
bus to the B bus or from the B bus to the A bus,
depending on the logic level at the
direction-control (DIR) input. The output-enable
(OE
) input can be used to disable the device so
that the buses are effectively isolated.
T o ensure the high-impedance state during power
up or power down, OE should be tied to V
through a pullup resistor; the minimum value of
the resistor is determined by the current-sinking
capability of the driver.
CC
SN74AHC245 . . . DB, DGV, DW, N, OR PW PACKAGE
SN54AHC245 ...J OR W PACKAGE
(TOP VIEW)
1
20
B8
19
18
17
16
15
14
13
12
11
V
B7
CC
V
OE
B1
B2
B3
B4
B5
B6
B7
B8
OE
18
17
16
15
14
B6
CC
B1
B2
B3
B4
B5
DIR
2
A1
3
A2
4
A3
5
A4
6
A5
7
A6
8
A7
9
A8
GND
SN54AHC245 . . . FK PACKAGE
10
(TOP VIEW)
A2A1DIR
A3
A4
A5
A6
A7
3212019
4
5
6
7
8
910111213
A8
GND
The SN54AHC245 is characterized for operation
over the full military temperature range of –55°C
to 125°C. The SN74AHC245 is characterized for
operation from –40°C to 85°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
EPIC is a trademark of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
FUNCTION TABLE
(each transceiver)
INPUTS
OE DIR
L L B data to A bus
L H A data to B bus
H X Isolation
Copyright 2000, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
1
SN54AHC245, SN74AHC245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCLS230G – OCTOBER 1995 – REVISED JANUARY 2000
logic symbol
†
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
†
OE
DIR
A1
A2
A3
A4
A5
A6
A7
A8
19
1
2
3
4
5
6
7
8
9
G3
3 EN1 [BA]
3 EN2 [AB]
1
2
logic diagram (positive logic)
1
DIR
18
17
16
15
14
13
12
11
B1
B2
B3
B4
B5
B6
B7
B8
A1
19
OE
2
18
B1
To Seven Other Channels
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
UNIT
mA
mA
∆t/∆vInput transition rise or fall rate
ns/V
SN54AHC245, SN74AHC245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCLS230G – OCTOBER 1995 – REVISED JANUARY 2000
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
†
Supply voltage range, VCC –0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, VI (see Note 1) –0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output voltage range, V
Input clamp current, I
Output clamp current, I
(see Note 1) –0.5 V to V
O
(V
IK
I
OK
Continuous output current, I
< 0) –20 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(V
< 0 or VO > VCC) ±20 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
O
(V
= 0 to VCC) ±25 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
O
O
CC
+ 0.5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through VCC or GND ±75 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance, θ
(see Note 2): DB package 70°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JA
DGV package 92°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DW package 58°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
N package 69°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package 83°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51.
–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
stg
recommended operating conditions (see Note 3)
SN54AHC245 SN74AHC245
MIN MAX MIN MAX
V
V
V
V
V
I
OH
I
OL
T
NOTE 3: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Supply voltage 2 5.5 2 5.5 V
CC
VCC = 2 V 1.5 1.5
High-level input voltage
IH
Low-level input voltage
IL
Input voltage OE or DIR 0 5.5 0 5.5 V
I
Output voltage A or B 0 V
O
High-level output current
Low-level output current
p
Operating free-air temperature –55 125 –40 85 °C
A
Implications of Slow or Floating CMOS Inputs
, literature number SCBA004.
VCC = 3 V
VCC = 5.5 V 3.85 3.85
VCC = 2 V 0.5 0.5
VCC = 3 V
VCC = 5.5 V 1.65 1.65
VCC = 2 V –50 –50
VCC = 3.3 V ± 0.3 V
VCC = 5 V ± 0.5 V –8 –8
VCC = 2 V 50 50
VCC = 3.3 V ± 0.3 V
VCC = 5 V ± 0.5 V 8 8
VCC = 3.3 V ± 0.3 V 100 100
VCC = 5 V ± 0.5 V 20 20
2.1 2.1
0.9 0.9
CC
–4 –4
4 4
0 V
CC
V
V
V
m
A
m
A
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
3
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