SN54ABT245, SN74ABT245A
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081E – JANUARY 1991 – REVISED JULY 1994
•
•
•
•
•
•
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.
The SN74ABT245A 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
SN74ABT245A 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
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
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), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages, Ceramic Chip Carriers (FK),
Ceramic Flat (W) Packages, and Plastic (N)
and Ceramic (J) DIPs
SN54ABT245 . . . J OR W PACKAGE
SN74ABT245A . . . DB, DW, N, OR PW 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)
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, SN74ABT245A
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081E – 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
SN74ABT245A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
PW package . . . . . . . . . . . . . . . . . . . 0.7 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,
except for the N package, which has a trace length of zero. 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
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ABT245, SN74ABT245A
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081E – JANUARY 1991 – REVISED JULY 1994
recommended operating conditions (see Note 3)
SN54ABT245
MIN
VCC
VIH
VIL
VI
IOH
IOL
∆t
/∆v
∆t
/∆VCC
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
Power-up ramp rate
– 55
125
0
4.5
2
0.8
VCC
– 24
48
5
200
– 40
85
0
MAX
5.5
SN74ABT245A
MIN
4.5
2
0.8
VCC
– 32
64
5
MAX
5.5
UNIT
V
V
V
V
mA
mA
ns / V
µs
/ V
°C
TA
Operating free-air temperature
NOTE 3: Unused or floating pins (input or I/O) must be held high or low.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
2–3
SN54ABT245, SN74ABT245A
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081E – JANUARY 1991 – REVISED JULY 1994
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V,
VCC = 5 V,
VCC = 4 5 V
4.5
VOL
II
IOZPU
IOZPD
IOZH‡
IOZL‡
Ioff
ICEX
IO§
ICC
Control inputs
A or B ports
VCC = 4 5 V
4.5
VCC = 0 to 5.5 V,
VCC = 2.1 V to 5.5 V,
VCC = 0 to 2.1 V,
VO = 0.5 V to 2.7 V,
VCC = 2.1 V to 0,
VO = 0.5 V to 2.7 V,
VCC = 2.1 V to 5.5 V,
OE
≥
2 V
VCC = 2.1 V to 5.5 V,
OE
≥
2 V
Outputs high
VCC = 0,
VCC = 5.5 V,
VCC = 5.5 V,
A or B ports
VCC = 5.5 V,
IO = 0,
VI = VCC or GND
VCC = 5.5 V,
,
One input at 3.4 V,
Other inputs at
VCC or GND
II = –18 mA
IOH = – 3 mA
IOH = – 3 mA
IOH = – 24 mA
IOH = – 32 mA
IOL = 48 mA
IOL = 64 mA
VI = VCC or GND
VI = VCC or GND
OE = X
OE = X
VO = 2.7 V,
VO = 0.5 V,
VI or VO
≤
4.5 V
VO = 5.5 V
VO = 2.5 V
Outputs high
Outputs low
Outputs disabled
Outputs enabled
Outputs disabled
– 50
–140
5
22
1
TA = 25°C
MIN TYP†
MAX
–1.2
2.5
3
2
2*
0.55
0.55*
±1
±
20
±
50
±
50
10
– 10
±100
50
–180
250
30
250
1.5
50
1.5
4
8
– 50
50
–180
250
30
250
1.5
50
1.5
– 50
10
– 10
±1
±
100
0.55
0.55
±1
±
20
±
50
±
50
10
– 10
±100
50
–180
250
30
250
1.5
50
1.5
2.5
3
2
2
V
µA
µA
µA
µA
µA
µA
µA
mA
µA
mA
µA
mA
µA
mA
pF
pF
SN54ABT245
MIN
MAX
–1.2
2.5
3
V
SN74ABT245A
MIN
MAX
–1.2
UNIT
V
VOH
Data inputs
∆I
CC¶
Control inputs
Ci
Cio
Control inputs
A or B ports
VCC = 5.5 V,
One input at 3.4 V,
Other inputs at VCC or GND
VI = 2.5 V or 0.5 V
VO = 2.5 V or 0.5 V
* 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.
§ 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.
2–4
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ABT245, SN74ABT245A
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCBS081E – 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)
SN54ABT245
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 5 V,
TA = 25°C
MIN
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
A or B
B or A
A or B
A or B
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
1
1
1
2
1.7
1.7
4.8
4.8
5.9
7.5
7.4
6.5
MIN
MAX
SN74ABT245A
VCC = 5 V,
TA = 25°C
MIN
1
1
2
1.9
2.2
1.5
TYP
2
2.6
3.5
4
4.4
3
MAX
3.2
3.5
4.5
5.3
5.4
4
1
1
2
1.9
2.2
1.5
3.6
3.9
5.6
6.2
5.9
4.5
ns
ns
ns
MIN
MAX
UNIT
OE
OE
† This data sheet limit may vary among suppliers.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
2–5
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