SN54AC245, SN74AC245
OCTAL BUS TRANSCEIVERS
WITH 3 STATE OUTPUTS
SCAS461F - FEBRUARY 1995 - REVISED OCTOBER 2003
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
2-V to 6-V V
CC
Operation
D
Inputs Accept Voltages to 6 V
D
Max t
pd
of 7 ns at 5 V
description/ordering information
The 'AC245 octal bus transceivers are designed
for asynchronous two-way communication
between data buses. The control-function
implementation minimizes external timing
requirements.
When the output-enable (OE) is low, the device
passes noninverted data 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.
A high on
OE
disables the device so that the buses
are effectively isolated.
To ensure the high-impedance state during power
up or power down, OE should be tied to V
CC
through a pullup resistor; the minimum value of
the resistor is determined by the current-sinking
capability of the driver.
ORDERING INFORMATION
TA
PACKAGE
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
PDIP - N
Tube
SN74AC245N
SN74AC245N
SOIC - DW
Tube
SN74AC245DW
AC245
SOIC - DW
Tape and reel
SN74AC245DWR
AC245
-40
C to 85
C
SOP - NS
Tape and reel
SN74AC245NSR
AC245
-40 C to 85 C
SSOP - DB
Tape and reel
SN74AC245DBR
AC245
TSSOP - PW
Tube
SN74AC245PW
AC245
TSSOP - PW
Tape and reel
SN74AC245PWR
AC245
CDIP - J
Tube
SNJ54AC245J
SNJ54AC245J
-55
C to 125
C
CFP - W
Tube
SNJ54AC245W
SNJ54AC245W
-55 C to 125 C
LCCC - FK
Tube
SNJ54AC245FK
SNJ54AC245FK
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are
available at www.ti.com/sc/package.
Copyright
2003, 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.
SN54AC245 . . . J OR W PACKAGE
SN74AC245 . . . DB, DW, N, NS, OR PW PACKAGE
(TOP VIEW)
3
2
1 20 19
9 10 11 12 13
4
5
6
7
8
18
17
16
15
14
B1
B2
B3
B4
B5
A3
A4
A5
A6
A7
SN54AC245 . . . FK PACKAGE
(TOP VIEW)
A2
A1
DIR
B7
B6
OE
A8
G
ND
B8
V
CC
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
DIR
A1
A2
A3
A4
A5
A6
A7
A8
GND
V
CC
OE
B1
B2
B3
B4
B5
B6
B7
B8
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.
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.
SN54AC245, SN74AC245
OCTAL BUS TRANSCEIVERS
WITH 3 STATE OUTPUTS
SCAS461F - FEBRUARY 1995 - REVISED OCTOBER 2003
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
FUNCTION TABLE
INPUTS
OPERATION
OE
DIR
OPERATION
L
L
H
L
H
X
B data to A bus
A data to B bus
Isolation
logic diagram (positive logic)
DIR
OE
A1
B1
1
2
18
19
To Seven Other Channels
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
-0.5 V to 7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, V
I
(see Note 1)
-0.5 V to V
CC
+ 0.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output voltage range, V
O
(see Note 1)
-0.5 V to V
CC
+ 0.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
IK
(V
I
< 0 or V
I
> V
CC
)
20 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output clamp current, I
OK
(V
O
< 0 or V
O
> V
CC
)
20 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous output current, I
O
(V
O
= 0 to V
CC
)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through V
CC
or GND
200 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance,
JA
(see Note 2): DB package
70
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DW package
58
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
N package
69
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NS package
60
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package
83
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
-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.
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 51-7.
SN54AC245, SN74AC245
OCTAL BUS TRANSCEIVERS
WITH 3 STATE OUTPUTS
SCAS461F - FEBRUARY 1995 - REVISED OCTOBER 2003
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
recommended operating conditions (see Note 3)
SN54AC245
SN74AC245
UNIT
MIN
MAX
MIN
MAX
UNIT
VCC
Supply voltage
2
6
2
6
V
VCC = 3 V
2.1
2.1
VIH
High-level input voltage
VCC = 4.5 V
3.15
3.15
V
VIH
High-level input voltage
VCC = 5.5 V
3.85
3.85
V
VCC = 3 V
0.9
0.9
VIL
Low-level input voltage
VCC = 4.5 V
1.35
1.35
V
VIL
Low-level input voltage
VCC = 5.5 V
1.65
1.65
V
VI
Input voltage
0
VCC
0
VCC
V
VO
Output voltage
0
VCC
0
VCC
V
VCC = 3 V
-12
-12
IOH
High-level output current
VCC = 4.5 V
-24
-24
mA
IOH
High-level output current
VCC = 5.5 V
-24
-24
mA
VCC = 3 V
12
12
IOL
Low-level output current
VCC = 4.5 V
24
24
mA
IOL
Low-level output current
VCC = 5.5 V
24
24
mA
D
t/
D
v
Input transition rise or fall rate
8
8
ns/V
TA
Operating free-air temperature
-55
125
-40
85
C
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,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
SN54AC245, SN74AC245
OCTAL BUS TRANSCEIVERS
WITH 3 STATE OUTPUTS
SCAS461F - FEBRUARY 1995 - REVISED OCTOBER 2003
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VCC
TA = 25
C
SN54AC245
SN74AC245
UNIT
PARAMETER
TEST CONDITIONS
VCC
MIN
TYP
MAX
MIN
MAX
MIN
MAX
UNIT
3 V
2.9
2.9
2.9
IOH = -50
m
A
4.5 V
4.4
4.4
4.4
IOH = -50
m
A
5.5 V
5.4
5.4
5.4
VOH
IOH = -12 mA
3 V
2.56
2.4
2.46
V
VOH
IOH = -24 mA
4.5 V
3.86
3.7
3.76
V
IOH = -24 mA
5.5 V
4.86
4.7
4.76
IOH = -50 mA
5.5 V
3.85
IOH = -75 mA
5.5 V
3.85
3 V
0.002
0.1
0.1
0.1
IOL = 50
m
A
4.5 V
0.001
0.1
0.1
0.1
IOL = 50
m
A
5.5 V
0.001
0.1
0.1
0.1
VOL
IOL = 12 mA
3 V
0.36
0.5
0.44
V
VOL
IOL = 24 mA
4.5 V
0.36
0.5
0.44
V
IOL = 24 mA
5.5 V
0.36
0.5
0.44
IOL = 50 mA
5.5 V
1.65
IOL = 75 mA
5.5 V
1.65
II
A or B ports
VI = VCC or GND
5.5 V
0.1
1
1
A
II
OE or DIR
VI = VCC or GND
5.5 V
0.1
1
1
m
A
IOZ
VO = VCC or GND,
VI(OE) = VIL or VIH
5.5 V
0.5
10
5
m
A
ICC
VI = VCC or GND, IO = 0
5.5 V
4
80
40
m
A
Ci
VI = VCC or GND
5 V
4.5
pF
Cio
VO = VCC or GND
5 V
15
pF
Not more than one output should be tested at a time, and the duration of the test should not exceed 2 ms.
For I/O ports, the parameter IOZ includes the input leakage current.
switching characteristics over recommended operating free-air temperature range,
V
CC
= 3.3 V
"
0.3 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
TO
TA = 25
C
SN54AC245
SN74AC245
UNIT
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
MIN
TYP
MAX
MIN
MAX
MIN
MAX
UNIT
tPLH
A or B
B or A
1.5
5
8.5
1
11.5
1
9
ns
tPHL
A or B
B or A
1.5
5
8.5
1
10
1
9
ns
tPZH
OE
A or B
2.5
7
11.5
1
13.5
2
12.5
ns
tPZL
OE
A or B
2.5
7.5
12
1
14.5
2
13.5
ns
tPHZ
OE
A or B
2
6.5
12
1
13.5
1
12.5
ns
tPLZ
OE
A or B
2
7
11.5
1
14
1.5
13
ns
SN54AC245, SN74AC245
OCTAL BUS TRANSCEIVERS
WITH 3 STATE OUTPUTS
SCAS461F - FEBRUARY 1995 - REVISED OCTOBER 2003
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range,
V
CC
= 5 V
"
5 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
TO
TA = 25
C
SN54AC245
SN74AC245
UNIT
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
MIN
TYP
MAX
MIN
MAX
MIN
MAX
UNIT
tPLH
A or B
B or A
1.5
3.5
6.5
1
8.5
1
7
ns
tPHL
A or B
B or A
1.5
3.5
6
1
7.5
1
7
ns
tPZH
OE
A or B
1.5
5
8.5
1
10
1
9
ns
tPZL
OE
A or B
1.5
5.5
9
1
10.5
1
9.5
ns
tPHZ
OE
A or B
1.5
5.5
9
1
10.5
1
10
ns
tPLZ
OE
A or B
1.5
5.5
9
1
10.5
1
10
ns
operating characteristics, V
CC
= 5 V, T
A
= 25
C
PARAMETER
TEST CONDITIONS
TYP
UNIT
Cpd
Power dissipation capacitance per transceiver
CL = 50 pF,
f = 1 MHz
45
pF
PARAMETER MEASUREMENT INFORMATION
tPHL
tPLH
tPLH
tPHL
Input
Out-of-Phase
Output
50%
50%
50% VCC
50% VCC
50% VCC
50% VCC
VCC
0 V
VOL
VOH
VOH
VOL
In-Phase
Output
VOLTAGE WAVEFORMS
From Output
Under Test
CL = 50 pF
(see Note A)
LOAD CIRCUIT
S1
2
VCC
500
500
Output
Control
(low-level
enabling)
Output
Waveform 1
S1 at 2
VCC
(see Note B)
Output
Waveform 2
S1 at Open
(see Note B)
VOL
VOH
tPZL
tPZH
tPLZ
tPHZ
50% VCC
50% VCC
VCC
0 V
50% VCC
VOL + 0.3 V
50% VCC
VOH - 0.3 V
0 V
VCC
Open
VOLTAGE WAVEFORMS
tPLH/tPHL
tPLZ/tPZL
tPHZ/tPZH
Open
2
VCC
Open
TEST
S1
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR
1 MHz, ZO = 50
, tr
v
2.5 ns, tf
v
2.5 ns.
D. The outputs are measured one at a time with one input transition per measurement.
Figure 1. Load Circuit and Voltage Waveforms
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