SN54F245, SN74F245
OPERATION
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDFS010A – MARCH 1987 – REVISED OCT OBER 1993
• 3-State Outputs Drive Bus Lines Directly
• Package Options Include Plastic
Small-Outline (SOIC) and Shrink
Small-Outline (SSOP) Packages, Ceramic
Chip Carriers, and Plastic and Ceramic
DIPs
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.
The SN74F245 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 SN54F245 is characterized for operation over
the full military temperature range of –55°C to
125°C. The SN74F245 is characterized for
operation from 0°C to 70°C.
SN54F245 ...J PACKAGE
SN74F245 . . . DB, DW, OR N PACKAGE
A3
A4
A5
A6
A7
(TOP VIEW)
DIR
1
A1
2
A2
3
A3
4
A4
5
A5
6
A6
7
A7
8
9
A8
GND
SN54F245 . . . FK PACKAGE
10
(TOP VIEW)
A2A1DIR
3212019
4
5
6
7
8
910 11 12 13
20
19
18
17
16
15
14
13
12
11
V
CC
V
OE
B1
B2
B3
B4
B5
B6
B7
B8
18
17
16
15
14
CC
B1
B2
B3
B4
B5
FUNCTION TABLE
INPUTS
OE DIR
L L B data to A bus
L H A data to B bus
H X Isolation
A8
GND
B8
B7
B6 OE
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
Copyright 1993, Texas Instruments Incorporated
2–1
SN54F245, SN74F245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDFS010A – MARCH 1987 – REVISED OCT OBER 1993
19
1
2
3
4
5
6
7
8
9
†
G3
3EN1[BA]
3EN2[AB]
1
2
18
17
16
15
14
13
12
11
logic diagram (positive logic)
1
DIR
B1
B2
B3
B4
B5
B6
B7
B8
A1
2
To Seven Other Channels
19
18
OE
B1
logic symbol
OE
DIR
A1
A2
A3
A4
A5
A6
A7
A8
†
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
Input voltage range, V
Input current range –30 mA to 5 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage range applied to any output in the disabled or power-off state –0.5 V to 5.5 V. . . . . . . . . . . . . . . . . . .
Voltage range applied to any output in the high state –0.5 V to V
Current into any output in the low state: SN54F245 (A1 thru A8) 40 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range: SN54F245 –55°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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 input voltage ratings may be exceeded provided the input current ratings are observed.
–0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CC
(except I/O ports) (see Note 1) –1.2 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN54F245 (B1 thru B8) 96 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74F245 (A1 thru A8) 48 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74F245 (B1 thru B8) 128 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74F245 0°C to 70°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
‡
CC
2–2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54F245, SN74F245
UNIT
IOHHigh-level output current
mA
IOLLow-level output current
mA
PARAMETER
TEST CONDITIONS
UNIT
A1 thru A8
V
V
B1 thru B8
V
V
A1 thru A8
V
4.5 V
V
V
B1 thru B8
V
V
I
V
V
mA
I
‡
V
5.5 V
V
2.7 V
A
I
‡
V
V
V
mA
I
§
V
V
0
mA
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDFS010A – MARCH 1987 – REVISED OCTOBER 1993
recommended operating conditions
SN54F245 SN74F245
MIN NOM MAX MIN NOM MAX
V
CC
V
IH
V
IL
I
IK
T
A
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
V
IK
V
OH
OL
I
IH
IL
OS
I
CC
†
All typical values are at VCC = 5 V, TA = 25°C.
‡
For I/O ports, the parameters IIH and IIL include the off-state output current.
§
Not more than one output should be shorted at a time, and the duration of the short circuit should not exceed one second.
Supply voltage 4.5 5 5.5 4.5 5 5.5 V
High-level input voltage 2 2 V
Low-level input voltage 0.8 0.8 V
Input clamp current –18 –18 mA
p
p
Operating free-air temperature –55 125 0 70 °C
VCC = 4.5 V, II = –18 mA –1.2 –1.2 V
= 4.5
CC
= 4.5
CC
Any output VCC = 4.75 V, IOH = –1 mA to – 3 mA 2.7
=
CC
= 4.5
CC
A and B
DIR, OE
A and B
DIR, OE
A and B
DIR, OE
A1 thru A8
B1 thru B8
= 5.5
CC
=
CC
= 5.5 V,
CC
= 5.5 V,
CC
VCC = 5.5 V
,
IOH = – 1 mA 2.5 3.4 2.5 3.4
IOH = – 3 mA 2.4 3.3 2.4 3.3
IOH = – 12 mA 2 3.2
IOH = – 15 mA 2 3.1
IOL = 20 mA 0.3 0.5
IOL = 24 mA 0.35 0.5
IOL = 48 mA 0.38 0.55
IOL = 64 mA 0.42 0.55
VI = 5.5 V 1 1
VI = 7 V 0.1 0.1
=
I
= 0.5
I
O
Outputs high 70 90 70 90
Outputs low 95 120 95 120
Outputs disabled 85 110 85 110
A1 thru A8 –3 –3
B1 thru B8 –12 –15
A1 thru A8 20 24
B1 thru B8 48 64
SN54F245 SN74F245
MIN TYP†MAX MIN TYP†MAX
70 70
20 20
–0.65 –0.65
– 1.2 – 1.2
=
–60 –150 –60 –150
–100 –225 –100 –225
V
µ
mA
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
2–3
SN54F245, SN74F245
(
)
(
)
(INPUT)
(OUTPUT)
A or B
B or A
ns
OE
A or B
ns
OE
A or B
ns
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDFS010A – MARCH 1987 – REVISED OCT OBER 1993
switching characteristics (see Note 2)
VCC = 5 V,
CL = 50 pF,
PARAMETER
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
†
NOTE 2: Load circuits and waveforms are shown in Section 1.
PLZ
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
FROM
INPUT
TO
OUTPUT
RL = 500 Ω,
TA = 25°C
′F245 SN54F245 SN74F245
MIN TYP MAX MIN MAX MIN MAX
1.7 3.8 6 1.2 7.5 1.7 7
1.7 4.2 6 1.2 7.5 1.7 7
2.2 4.9 7 1.7 9 2.2 8
2.7 5.6 8 2.2 10 2.7 9
2.2 4.6 6.5 1.7 9 2.2 7.5
1.2 4.6 6.5 1.2 10 1.2 7.5
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500Ω,
TA = MIN to MAX
†
UNIT
2–4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
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Copyright 1998, Texas Instruments Incorporated
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