SN54ABT245, SN74ABT245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081D – JANUARY 1991 – REVISED JULY 1994
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State-of-the-Art
EPIC-
ΙΙ
B
™
BiCMOS Design
Significantly Reduces Power Dissipation
ESD Protection Exceeds 2000 V Per
MIL-STD-883C, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
Latch-Up Performance Exceeds 500 mA
Per JEDEC Standard JESD-17
Typical V
OLP
(Output Ground Bounce)
< 1 V at V
CC
= 5 V, T
A
= 25°C
High-Drive Outputs (– 32-mA I
OH
,
64-mA I
OL
)
Package Options Include Plastic
Small-Outline (DW) and Shrink
Small-Outline (DB) Packages, Ceramic Chip
Carriers (FK), and Plastic (N) and
Ceramic (J) DIPs
SN54ABT245 . . . J PACKAGE
SN74ABT245 . . . DB, DW, OR N 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
SN54ABT245 . . . FK PACKAGE
(TOP VIEW)
A2
A1
DIR
V
CC
A3
A4
A5
A6
A7
description
These octal bus transceivers are designed for
asynchronous communication between data
buses. The devices transmit data 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 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.
4
5
6
7
8
3 2 1 20 19
18
17
16
15
14
9 10 11 12 13
OE
B1
B2
B3
B4
B5
The SN74ABT245 is available in TI’s shrink small-outline package (DB), which provides the same I/O pin count
and functionality of standard small-outline packages in less than half the printed-circuit-board area.
The SN54ABT245 is characterized for operation over the full military temperature range of – 55°C to 125°C. The
SN74ABT245 is characterized for operation from – 40°C to 85°C.
FUNCTION TABLE
INPUTS
OE
L
L
H
DIR
L
H
X
OPERATION
B data to A bus
A data to B bus
Isolation
EPIC-ΙΙB 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.
Copyright
©
1994, Texas Instruments Incorporated
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
A8
GND
B8
B7
B6
2–1
SN54ABT245, SN74ABT245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081D – JANUARY 1991 – REVISED JULY 1994
logic symbol
†
OE
DIR
19
1
G3
3EN1[BA]
3EN2[AB]
1
2
A2
A3
A4
A5
A6
A7
A8
3
4
5
6
7
8
9
17
16
15
14
13
12
11
B2
B3
B4
B5
B6
B7
B8
18
B1
logic diagram (positive logic)
DIR
1
19
OE
A1
2
A1
2
18
B1
To Seven Other Channels
† This symbol is in accordance with ANSI/IEEE Std 91-1984
and IEC Publication 617-12.
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
(except I/O ports) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.5 V to 7 V
Voltage applied to any output in the high state or power-off state, V
O
. . . . . . . . . . . . . . . . . . . . . – 0.5 V to 5.5 V
Current into any output in the low state, I
O
: SN54ABT245 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 mA
SN74ABT245 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 mA
Input clamp current, I
IK
(V
I
< 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –18 mA
Output clamp current, I
OK
(V
O
< 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 50 mA
Maximum power dissipation at T
A
= 55°C (in still air) (see Note 2): DB package . . . . . . . . . . . . . . . . . . . . 0.6 W
DW package . . . . . . . . . . . . . . . . . . . 1.6 W
N package . . . . . . . . . . . . . . . . . . . . . 1.3 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.
NOTES: 1. The input and output negative-voltage ratings may be exceeded if the input and output clamp-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.
For more information, refer to the
Package Thermal Considerations
application note in the 1994
ABT Advanced BiCMOS Technology
Data Book,
literature number SCBD002B.
2–2
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DALLAS, TEXAS 75265
SN54ABT245, SN74ABT245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081D – JANUARY 1991 – REVISED JULY 1994
recommended operating conditions (see Note 3)
SN54ABT245
MIN
VCC
VIH
VIL
VI
IOH
IOL
∆t
/∆v
Supply voltage
High-level input voltage
Low-level input voltage
Input voltage
High-level output current
Low-level output current
Input transition rise or fall rate
– 55
0
4.5
2
0.8
VCC
– 24
48
5
125
– 40
0
MAX
5.5
SN74ABT245
MIN
4.5
2
0.8
VCC
– 32
64
5
85
MAX
5.5
UNIT
V
V
V
V
mA
mA
ns / V
°C
TA
Operating free-air temperature
NOTE 3: Unused or floating pins (input or I/O) must be held high or low.
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VCC = 4.5 V,
VCC = 4.5 V,
VCC = 5 V,
VCC = 4 5 V
4.5
VOL
II
IOZH‡
IOZL‡
Ioff
ICEX
IO¶
ICC
VCC = 4 5 V
4.5
VCC = 5.5 V,
,
VI = VCC or GND
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 0,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
IO = 0,
VI = VCC or GND
VCC = 5.5 V,
One input at 3.4 V
O i
V,
Other inputs at
in uts
VCC or GND
VI = 2.5 V or 0.5 V
VO = 2.5 V or 0.5 V
VO = 2.7 V
VO = 0.5 V
VI or VO
≤
4.5 V
VO = 5.5 V
Outputs high
VO = 2.5 V
Outputs high
A or B ports
Outputs low
Outputs disabled
Outputs enabled
Data inputs
Control inputs
Control inputs
A or B ports
4
8
Outputs disabled
– 50
–140
5
22
1
TEST CONDITIONS
II = –18 mA
IOH = – 3 mA
IOH = – 3 mA
IOH = – 24 mA
IOH = – 32 mA
IOL = 48 mA
IOL = 64 mA
Control inputs
A or B ports
TA = 25°C
MIN TYP†
MAX
–1.2
2.5
3
2
2*
0.55
0.55*
±1
±100
10§
– 10§
±100
50
–180
250
30
250
1.5
50
1.5
– 50
50
–180
250
30
250
1.5
50
1.5
– 50
±1
±100
10§
– 10§
0.55
0.55
±1
±100
10§
– 10§
±100
50
–180
250
30
250
1.5
50
1.5
2.5
3
2
2
V
µA
µA
µA
µA
µA
mA
µA
mA
µA
mA
µA
mA
pF
pF
SN54ABT245
MIN
MAX
–1.2
2.5
3
V
SN74ABT245
MIN
MAX
–1.2
UNIT
V
VOH
∆I
CC#
Ci
Cio
* On products compliant to MIL-STD-883, Class B, this parameter does not apply.
† All typical values are at VCC = 5 V.
‡ The parameters IOZH and IOZL include the input leakage current.
§ This data sheet limit may vary among suppliers.
¶ Not more than one output should be tested at a time, and the duration of the test should not exceed one second.
# This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND.
POST OFFICE BOX 655303
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DALLAS, TEXAS 75265
2–3
SN54ABT245, SN74ABT245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081D – JANUARY 1991 – REVISED JULY 1994
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature, C
L
= 50 pF (unless otherwise noted) (see Figure 1)
PARAMETER
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
FROM
(INPUT)
A or B
TO
(OUTPUT)
B or A
A or B
A or B
VCC = 5 V,
TA = 25°C
MIN
1
1
1.3
2.3
1.7†
1.7†
TYP
2.6
2.9
3.3
4.3
4.7
4.3
MAX
4.1
4.2
4.8
5.8
6.2
5.8
SN54ABT245
MIN
1
1
1
2
1.7
1.7
MAX
4.8
4.8
5.9
7.5
7.4
6.5
SN74ABT245
MIN
1
1
1.3
2.3
1.7†
1.7†
MAX
4.6
4.6
5.3
6.3
7.2
6.3
ns
ns
ns
UNIT
OE
OE
† This data sheet limit may vary among suppliers.
2–4
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ABT245, SN74ABT245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081D – JANUARY 1991 – REVISED JULY 1994
PARAMETER MEASUREMENT INFORMATION
7V
From Output
Under Test
CL = 50 pF
(see Note A)
500
Ω
S1
Open
GND
500
Ω
TEST
tPLH/tPHL
tPLZ/tPZL
tPHZ/tPZH
S1
Open
7V
Open
LOAD CIRCUIT FOR OUTPUTS
3V
Timing Input
tw
3V
Input
1.5 V
1.5 V
0V
VOLTAGE WAVEFORMS
PULSE DURATION
Data Input
tsu
1.5 V
th
3V
1.5 V
0V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
1.5 V
0V
Input
(see Note B)
tPLH
Output
3V
1.5 V
1.5 V
0V
tPHL
VOH
1.5 V
1.5 V
VOL
tPHL
tPLH
VOH
1.5 V
1.5 V
VOL
Output
Control
tPZL
Output
Waveform 1
S1 at 7 V
(see Note C)
Output
Waveform 2
S1 at Open
(see Note C)
tPZH
3V
1.5 V
1.5 V
0V
tPLZ
1.5 V
tPHZ
VOH – 0.3 V
VOH
3.5 V
VOL + 0.3 V
VOL
Output
1.5 V
[
0V
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
INVERTING AND NONINVERTING OUTPUTS
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES
LOW- AND HIGH-LEVEL ENABLING
NOTES: A. CL includes probe and jig capacitance.
B. All input pulses are supplied by generators having the following characteristics: PRR
≤
10 MHz, ZO = 50
Ω,
tr
≤
2.5 ns, tf
≤
2.5 ns.
C. 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.
D. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuit and Voltage Waveforms
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2–5
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