74AC11245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS010B – JULY 1987 – REVISED APRIL 1996
D
D
D
D
D
D
DB, DW, NT, OR PW PACKAGE
(TOP VIEW)
3-State Outputs Drive Bus Lines Directly
Flow-Through Architecture Optimizes
PCB Layout
Center-Pin VCC and GND Configurations
Minimize High-Speed Switching Noise
EPIC t (Enhanced-Performance Implanted
CMOS) 1-mm Process
500-mA Typical Latch-Up Immunity at
125°C
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages, and Standard Plastic 300-mil
DIPs (NT)
A1
A2
A3
A4
GND
GND
GND
GND
A5
A6
A7
A8
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
DIR
B1
B2
B3
B4
VCC
VCC
B5
B6
B7
B8
OE
description
This octal bus transceiver is designed for asynchronous two-way communication between data buses. The
control-function implementation minimizes external timing requirements.
The device allows noninverted 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.
The 74AC11245 is characterized for operation from –40°C to 85°C.
FUNCTION TABLE
DIRECTION
CONTROL
DIR
OPERATION
L
L
B data to A bus
L
H
A data to B bus
H
X
Isolation
OUTPUT
ENABLE
OE
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.
Copyright 1996, 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.
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1
74AC11245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS010B – JULY 1987 – REVISED APRIL 1996
logic symbol†
OE
DIR
13
G3
24
3 EN1 [BA]
3 EN2 [AB]
A1
A2
A3
A4
A5
A6
A7
A8
1
23
1
2
2
22
3
21
4
20
9
17
10
16
11
15
12
14
† This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
logic diagram (positive logic)
DIR
24
13
A1
23
A2
B7
12
14
2
B6
11
15
A8
B5
10
16
A7
B4
9
17
A6
B3
4
20
A5
B2
3
21
A4
B1
2
22
A3
OE
1
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B8
B1
B2
B3
B4
B5
B6
B7
B8
74AC11245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS010B – JULY 1987 – REVISED APRIL 1996
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 VCC + 0.5 V
Output voltage range, VO (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VCC + 0.5 V
Input clamp current, IIK (VI < 0 or VI > VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA
Output clamp current, IOK (VO < 0 or VO > VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±50 mA
Continuous output current, IO (VO = 0 to VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±50 mA
Continuous current through VCC or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±200 mA
Maximum power dissipation at TA = 55°C (in still air) (see Note 2): DB package . . . . . . . . . . . . . . . . . . 0.65 W
DW package . . . . . . . . . . . . . . . . . . 1.7 W
NT package . . . . . . . . . . . . . . . . . . . 1.3 W
PW package . . . . . . . . . . . . . . . . . . . 0.7 W
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –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 maximum package power dissipation is calculated using a junction temperature of 150_C and a board trace length of 750 mils,
except for the NT package, which has a trace length of zero.
recommended operating conditions
VCC
VIH
Supply voltage
VCC = 3 V
VCC = 4.5 V
High-level input voltage
VCC = 5.5 V
VCC = 3 V
VIL
VI
VO
IOH
IOL
Dt/Dv
TA
Low-level input voltage
MIN
NOM
MAX
3
5
5.5
V
3.15
3.85
0.9
1.35
V
1.65
Input voltage
0
Output voltage
0
VCC = 3 V
VCC = 4.5 V
Low-level output current
V
2.1
VCC = 4.5 V
VCC = 5.5 V
High-level output current
UNIT
VCC
VCC
V
V
–4
–24
VCC = 5.5 V
VCC = 3 V
–24
VCC = 4.5 V
VCC = 5.5 V
24
mA
12
mA
24
Input transition rise or fall rate
0
10
ns/V
Operating free-air temperature
–40
85
°C
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3
74AC11245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS010B – JULY 1987 – REVISED APRIL 1996
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VCC
IOH = –50 mA
VOH
IOH = –4 mA
IOH = –24
24 mA
IOH = –75 mA{
IOL = 12 mA
IOL = 24 mA
II
A or B ports‡
OE or DIR
ICC
Ci
TA = 25°C
TYP
MAX
2.9
2.9
4.5 V
4.4
4.4
5.5 V
5.4
5.4
3V
2.58
2.48
4.5 V
3.94
3.8
5.5 V
4.94
4.8
3.85
0.1
4.5 V
0.1
0.1
5.5 V
0.1
0.1
3V
0.36
0.44
4.5 V
0.36
0.44
5.5 V
0.36
0.44
VO = VCC or GND
55V
5.5
UNIT
V
0.1
5.5 V
IO = 0
MAX
3V
IOL = 75 mA{
VI = VCC or GND,
VI = VCC or GND
MIN
3V
5.5 V
IOL = 50 mA
VOL
MIN
V
1.65
5.5 V
5V
±0.5
±5
±0.1
±1
8
80
4
mA
mA
pF
Cio
VO = VCC or GND
5V
12
† Not more than one output should be tested at a time, and the duration of the test should not exceed 10 ms.
‡ For I/O ports, the parameter IOZ includes the input leakage current.
pF
switching characteristics over recommended operating free-air temperature range,
VCC = 3.3 V ± 0.3 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A or B
B or A
tPZH
tPZL
OE
B or A
tPHZ
tPLZ
OE
B or A
MIN
TA = 25°C
TYP
MAX
MIN
MAX
1.5
6.5
11.2
1.5
12.5
1.5
5.7
8.5
1.5
9.7
1.5
8.6
14.2
1.5
15.9
1.5
8.2
11.5
1.5
12.7
1.5
7.7
10.5
1.5
11.3
1.5
8.5
12
1.5
13
UNIT
ns
ns
ns
switching characteristics over recommended operating free-air temperature range,
VCC = 5 V ± 0.5 V (unless otherwise noted) (see Figure 1)
4
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A or B
B or A
tPZH
tPZL
OE
B or A
tPHZ
tPLZ
OE
B or A
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TA = 25°C
MIN
TYP
MAX
MIN
MAX
1.5
4.8
8.5
1.5
9.5
1.5
4.1
6.3
1.5
6.9
1.5
6.2
10.2
1.5
11.4
1.5
5.9
8.6
1.5
9.5
1.5
6.4
8.8
1.5
9.5
1.5
7
9.6
1.5
10.4
UNIT
ns
ns
ns
74AC11245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS010B – JULY 1987 – REVISED APRIL 1996
operating characteristics, VCC = 5 V, TA = 25°C
PARAMETER
Cpd
d
TEST CONDITIONS
Outputs enabled
Power dissipation capacitance per transceiver
Outputs disabled
pF
CL = 50 pF,
TYP
f = 1 MHz
64
16
UNIT
pF
PARAMETER MEASUREMENT INFORMATION
2 × VCC
S1
500 Ω
From Output
Under Test
GND
Output
Control
(low-level
enabling)
LOAD CIRCUIT
VCC
50%
50%
0V
tPLH
tPHL
VOH
Output
S1
tPLH /tPHL
tPLZ /tPZL
tPHZ /tPZH
Open
2 × VCC
GND
50%
50%
500 Ω
CL = 50 pF
(see Note A)
Input
TEST
Open
50% VCC
50% VCC
VOL
VCC
0V
tPZL
Output
Waveform 2
S1 at GND
(see Note B)
[ VCC
tPLZ
Output
Waveform 1
S1 at 2 × VCC
(see Note B)
50% VCC
VOL
tPHZ
tPZH
VOLTAGE WAVEFORMS
20% VCC
50% VCC
80% VCC
VOH
[0V
VOLTAGE WAVEFORMS
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 Ω, tr = 3 ns, tf = 3 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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