SN54ALS245A, SN54AS245, SN74ALS245A, SN74AS245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS272A – NOVEMBER 1994 – REVISED JANUARY 2003
D
D
4.5-V to 5.5-V V
CC
Operation
Max t
pd
of 5.5 ns at 5 V
SN54ALS245A . . . J OR W PACKAGE
SN54AS245 . . . J PACKAGE
SN74ALS245A . . . DB, DW, N, OR NS PACKAGE
SN74AS245 . . . DW, N, OR NS PACKAGE
(TOP VIEW)
D
D
3-State Outputs Drive Bus Lines Directly
pnp Inputs Reduce dc Loading
SN54ALS245A, SN54AS245 . . . FK PACKAGE
(TOP VIEW)
DIR
A1
A2
A3
A4
A5
A6
A7
A8
GND
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
CC
OE
B1
B2
B3
B4
B5
B6
B7
B8
A2
A1
DIR
VCC
OE
A3
A4
A5
A6
A7
4
5
6
7
8
3 2 1 20 19
18
17
16
15
14
9 10 11 12 13
B1
B2
B3
B4
B5
description/ordering information
ORDERING INFORMATION
TA
PACKAGE†
ORDERABLE
PART NUMBER
SN74ALS245A-1N
PDIP – N
Tube
Tube
Tape and reel
0°C to 70°C
SOIC – DW
Tube
Tape and reel
Tube
Tape and reel
Tape and reel
SOP – NS
SSOP – DB
CDIP – J
–55°C to 125°C
CFP – W
LCCC – FK
Tape and reel
Tape and reel
Tape and reel
Tube
Tube
Tube
SN74ALS245AN
SN74AS245N
SN74ALS245ADW
SN74ALS245ADWR
SN74ALS245A-1DW
SN74ALS245A-1DWR
SN74AS245DW
SN74AS245DWR
SN74ALS245ANSR
SN74ALS245A-1NSR
SN74AS245NSR
SN74ALS245ADBR
SNJ54ALS245AJ
SNJ54AS245J
SNJ54ALS245AW
SNJ54ALS245AFK
SNJ54AS245FK
TOP-SIDE
MARKING
SN74ALS245A-1N
SN74ALS245AN
SN74AS245N
ALS245A
ALS245A 1
ALS245A-1
AS245
ALS245A
ALS245A-1
74AS245
G245A
SNJ54ALS245AJ
SNJ54AS245J
SNJ54ALS245AW
SNJ54ALS245AFK
SNJ54AS245FK
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.
Copyright
2003, 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.
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
A8
GND
B8
B7
B6
1
SN54ALS245A, SN54AS245, SN74ALS245A, SN74AS245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS272A – NOVEMBER 1994 – REVISED JANUARY 2003
description/ordering information(continued)
These octal bus transceivers are designed for asynchronous two-way communication between data buses. The
control-function implementation minimizes external timing requirements.
The devices allow 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 output-enable (OE) input can be used to disable the
device so that the buses are effectively isolated.
The -1 version of the SN74ALS245A is identical to the standard version, except that the recommended
maximum I
OL
is increased to 48 mA. There is no -1 version of the SN54ALS245A.
FUNCTION TABLE
INPUTS
OE
L
L
H
DIR
L
H
X
OPERATION
B data to A bus
A data to B bus
Isolation
logic diagram, each gate (positive logic)
DIR
1
19
OE
A1
2
18
B1
To Seven Other Channels
absolute maximum ratings over operating free-air temperature range (SN54ALS245A,
SN74ALS245A) (unless otherwise noted)
†
Supply voltage, V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, V
I
: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Package thermal impedance,
θ
JA
(see Note 1): DB package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70°C/W
DW package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58°C/W
N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69°C/W
NS package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60°C/W
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C
† 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.
NOTE 1: The package thermal impedance is calculated in accordance with JESD 51-7.
2
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ALS245A, SN54AS245, SN74ALS245A, SN74AS245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS272A – NOVEMBER 1994 – REVISED JANUARY 2003
recommended operating conditions (see Note 2)
SN54ALS245A
MIN
VCC
VIH
VIL
IOH
IOL
Supply voltage
High-level input voltage
Low-level input voltage
High-level output current
Low-level
Low level output current
4.5
2
0.7
– 12
12
NOM
5
MAX
5.5
SN74ALS245A
MIN
4.5
2
0.8
– 15
24
48†
NOM
5
MAX
5.5
UNIT
V
V
V
mA
mA
TA
Operating free-air temperature
– 55
125
0
70
°C
† Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
NOTE 2: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs,
literature number SCBA004.
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
VCC = 4.5 V
II = – 18 mA
IOH = – 0.4 mA
IOH = – 3 mA
IOH = – 12 mA
IOH = – 15 mA
IOL= 12 mA
VOL
Control inputs
A or B ports
Control inputs
A or B ports§
Control inputs
A or B ports§
VCC = 4.5 V
IOL = 24 mA
IOL = 48 mA†
VI = 7 V
VI = 5.5 V
VI = 2 7 V
2.7
VI = 0 4 V
0.4
VO = 2.25 V
Outputs high
Outputs low
Outputs disabled
– 20
30
36
38
0.1
0.1
20
20
– 0.1
– 0.1
–112
48
60
63
– 30
30
36
38
SN54ALS245A
MIN TYP‡
MAX
–1.5
VCC – 2
2.4
2
2
0.25
0.4
0.25
0.35
0.35
0.4
0.5
0.5
0.1
0.1
20
20
– 0.1
– 0.1
–112
45
55
58
mA
mA
µA
mA
mA
V
3.2
VCC – 2
2.4
3.2
SN74ALS245A
MIN TYP‡
MAX
–1.5
UNIT
V
VOH
V
II
IIH
IIL
IO¶
ICC
VCC = 5 5 V
5.5
VCC = 5 5 V
5.5 V,
VCC = 5 5 V
5.5 V,
VCC = 5.5 V,
VCC = 5.5 V
† Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
‡ All typical values are VCC = 5 V, TA = 25°C.
§ For I/O ports, the parameters IIH and IIL include the off-state output current.
¶ The output conditions have been chosen to produce a current that closely approximates one-half of the true short-circuit output current, IOS.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
3
SN54ALS245A, SN54AS245, SN74ALS245A, SN74AS245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS272A – NOVEMBER 1994 – REVISED JANUARY 2003
switching characteristics (see Figure 1)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
Ω,
R2 = 500
Ω,
TA = MIN to MAX†
SN54ALS245A SN74ALS245A
MIN
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
A or B
B or A
A or B
A or B
1
1
2
2
2
2
MAX
19
14
30
29
14
30
MIN
3
3
5
5
2
4
MAX
10
10
20
20
10
15
ns
ns
ns
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
UNIT
OE
OE
† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
absolute maximum ratings over operating free-air temperature range (SN54AS245, SN74AS245)
(unless otherwise noted)
‡
Supply voltage, V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, V
I
: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Package thermal impedance,
θ
JA
(see Note 1): DW package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58°C/W
N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69°C/W
NS package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60°C/W
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C
‡ 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.
NOTE 1: The package thermal impedance is calculated in accordance with JESD 51-7.
recommended operating conditions (see Note 2)
SN54AS245
MIN
VCC
VIH
VIL
IOH
IOL
TA
Supply voltage
High-level input voltage
Low-level input voltage
High-level output current
Low-level output current
Operating free-air temperature
– 55
4.5
2
0.8
– 12
48
125
0
NOM
5
MAX
5.5
SN74AS245
MIN
4.5
2
0.8
– 15
64
70
NOM
5
MAX
5.5
UNIT
V
V
V
mA
mA
°C
NOTE 2: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs,
literature number SCBA004.
4
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ALS245A, SN54AS245, SN74ALS245A, SN74AS245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS272A – NOVEMBER 1994 – REVISED JANUARY 2003
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
VCC = 4.5 V
II = – 18 mA
IOH = – 2 mA
IOH = – 3 mA
IOH = – 12 mA
IOH = – 15 mA
IOL = 48 mA
IOL = 64 mA
VI = 7 V
VI = 5.5 V
VI = 2 7 V
2.7
VI = 0 4 V
0.4
VO = 2.25 V
Outputs high
Outputs low
Outputs disabled
– 50
62
95
79
SN54AS245
MIN TYP†
MAX
–1.2
VCC – 2
2.4
2
2
0.3
0.55
0.35
0.1
0.1
50
70
– 0.5
– 0.75
– 150
97
143
123
– 50
62
95
79
0.55
0.1
0.1
20
70
– 0.5
– 0.75
– 150
97
143
123
mA
V
mA
µA
mA
mA
3.2
VCC – 2
2.4
3.2
SN74AS245
MIN TYP†
MAX
–1.2
UNIT
V
VOH
V
VOL
II
IIH
IIL
IO§
ICC
Control inputs
A or B ports
Control inputs
A or B ports‡
Control inputs
A or B ports‡
VCC = 4 5 V
4.5
VCC = 5 5 V
5.5
VCC = 5 5 V
5.5 V,
VCC = 5 5 V
5.5 V,
VCC = 5.5 V,
VCC = 5.5 V
† All typical values are VCC = 5 V, TA = 25°C.
‡ For I/O ports, the parameters IIH and IIL include the off-state output current.
§ The output conditions have been chosen to produce a current that closely approximates one-half of the true short-circuit output current, IOS.
switching characteristics (see Figure 1)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
Ω,
R2 = 500
Ω,
TA = MIN to MAX
¶
SN54AS245
SN74AS245
MIN
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
A or B
B or A
A or B
A or B
2
2
2
2
2
2
MAX
9.5
9
11
10.5
7.5
12
MIN
2
2
2
2
2
2
MAX
7.5
7
9
8.5
5.5
9.5
ns
ns
ns
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
UNIT
OE
OE
¶ For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
5
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