74ABT245 — Octal Bi-Directional Transceiver with 3-STATE Outputs
December 2007
74ABT245
Octal Bi-Directional Transceiver with 3-STATE Outputs
Features
■
Bidirectional non-inverting buffers
■
A and B output sink capability of 64mA, source
■
■
■
■
■
■
■
■
General Description
The ABT245 contains eight non-inverting bidirectional
buffers with 3-STATE outputs and is intended for bus-
oriented applications. Current sinking capability is 64 mA
on both the A and B ports. The Transmit/Receive (T/R)
input determines the direction of data flow through the
bidirectional transceiver. Transmit (active HIGH) enables
data from A Ports to B Ports; Receive (active LOW)
enables data from B Ports to A Ports. The Output Enable
input, when HIGH, disables both A and B ports by plac-
ing them in a HIGH Z condition.
capability of 32mA
Guaranteed output skew
Guaranteed multiple output switching specifications
Output switching specified for both 50pF and 250pF
loads
Guaranteed simultaneous switching, noise level and
dynamic threshold performance
Guaranteed latchup protection
High-impedance, glitch-free bus loading during entire
power up and power down cycle
Nondestructive, hot-insertion capability
Disable time is less than enable time to avoid bus
contention
Ordering Information
Order Number
74ABT245CSC
74ABT245CSJ
74ABT245CMSA
74ABT245CMTC
Package
Number
M20B
M20D
MSA20
MTC20
Package Description
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013,
0.300" Wide
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
20-Lead Shrink Small Outline Package (SSOP), JEDEC MO-150,
5.3mm Wide
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC
MO-153, 4.4mm Wide
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering number.
All packages are lead free per JEDEC: J-STD-020B standard.
©1991 Fairchild Semiconductor Corporation
74ABT245 Rev. 1.5.0
www.fairchildsemi.com
74ABT245 — Octal Bi-Directional Transceiver with 3-STATE Outputs
Connection Diagram
Logic Symbol
Truth Table
Inputs
OE
L
L
T/R
L
H
X
Output
Bus B Data to Bus A
Bus A Data to Bus B
HIGH Z State
Pin Descriptions
Pin Names
OE
T/R
A
0
–A
7
B
0
–B
7
H
Description
Output Enable Input (Active LOW)
Transmit/Receive Input
Side A Inputs or 3-STATE Outputs
Side B Inputs or 3-STATE Outputs
H
=
HIGH Voltage Level
L
=
LOW Voltage Level
X
=
Immaterial
Logic Diagram
©1991 Fairchild Semiconductor Corporation
74ABT245 Rev. 1.5.0
www.fairchildsemi.com
2
74ABT245 — Octal Bi-Directional Transceiver with 3-STATE Outputs
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.
The absolute maximum ratings are stress ratings only.
Symbol
T
STG
T
A
T
J
V
CC
V
IN
I
IN
V
O
Storage Temperature
Parameter
Ambient Temperature Under Bias
Junction Temperature Under Bias
V
CC
Pin Potential to Ground Pin
Input Voltage
(1)
Input Current
(1)
Voltage Applied to Any Output
Disabled or Power-off State
HIGH State
Current Applied to Output in LOW State
DC Latchup Source Current
Over Voltage Latchup (I/O)
Rating
–65°C to +150°C
–55°C to +125°C
–55°C to +150°C
–0.5V to +7.0V
–0.5V to +7.0V
–30mA to +5.0mA
–0.5V to 5.5V
–0.5V to V
CC
twice the rated I
OL
(mA)
–500mA
10V
Note:
1. Either voltage limit or current limit is sufficient to protect inputs.
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to absolute maximum ratings.
Symbol
T
A
V
CC
∆
V /
∆
t
Supply Voltage
Minimum Input Edge Rate
Data Input
Enable Input
Parameter
Free Air Ambient Temperature
Rating
–40°C to +85°C
+4.5V to +5.5V
50mV/ns
20mV/ns
©1991 Fairchild Semiconductor Corporation
74ABT245 Rev. 1.5.0
www.fairchildsemi.com
3
74ABT245 — Octal Bi-Directional Transceiver with 3-STATE Outputs
DC Electrical Characteristics
Symbol
V
IH
V
IL
V
CD
V
OH
V
OL
I
IH
I
BVI
I
BVIT
I
IL
V
ID
Parameter
Input HIGH Voltage
Input LOW Voltage
Input Clamp Diode Voltage
Output HIGH Voltage
Output LOW Voltage
Input HIGH Current
Input HIGH Current Breakdown
Test
Input HIGH Current Breakdown
Test (I/O)
Input LOW Current
Input Leakage Test
V
CC
Conditions
Recognized HIGH Signal
Recognized LOW Signal
Min.
2.0
Typ.
Max.
0.8
–1.2
Units
V
V
V
V
Min.
Min.
Min.
Min.
Max.
Max.
Max.
Max.
0.0
0–5.5V
0–5.5V
Max.
Max.
0.0
Max.
Max.
Max.
Max.
I
IN
=
–18 mA (OE, T/R)
I
OH
=
–3 mA (A
n
, B
n
)
I
OH
=
–32 mA (A
n
, B
n
)
I
OL
=
64 mA (A
n
, B
n
)
V
IN
=
2.7V (OE, T/R)
V
IN
=
V
CC
(OE, T/R)
V
IN
=
7.0V (OE, T/R)
V
IN
=
5.5V (A
n
, B
n
)
V
IN
=
0.5V (OE, T/R)
V
IN
=
0.0V (OE, T/R)
I
ID
=
1.9 µA (OE, T/R),
All Other Pins Grounded
V
OUT
=
2.7V (A
n
, B
n
),
OE
=
2.0V
V
OUT
=
0.5V (A
n
, B
n
),
OE
=
2.0V
V
OUT
=
0.0V (A
n
, B
n
)
V
OUT
=
V
CC
(A
n
, B
n
)
V
OUT
=
5.5V (A
n
, B
n
),
All Others GND
All Outputs HIGH
All Outputs LOW
OE
=
V
CC
, T/R
=
GND or
V
CC
, All Other GND or V
CC
V
I
=
V
CC
– 2.1V
OE, T/R V
I
=
V
CC
– 2.1V
Data Input V
I
=
V
CC
– 2.1V,
All Others at V
CC
or GND.
–100
4.75
2.5
2.0
0.55
1
1
7
100
–1
–1
V
µA
µA
µA
µA
V
I
IH
+ I
OZH
Output Leakage Current
I
IL
+ I
OZL
Output Leakage Current
I
OS
I
CEX
I
ZZ
I
CCH
I
CCL
I
CCZ
I
CCT
Output Short-Circuit Current
Output HIGH Leakage Current
Bus Drainage Test
Power Supply Current
Power Supply Current
Power Supply Current
Additional
I
CC
/Input
Outputs Enabled
Outputs 3-STATE
Outputs 3-STATE
I
CCD
Dynamic I
CC
No Load
10
–10
–275
50
100
50
30
50
2.5
2.5
50
0.1
µA
µA
mA
µA
µA
µA
mA
µA
mA
mA
µA
mA/
MHz
Max.
Outputs Open, OE
=
GND,
T/R
=
GND or V
CC
,
One Bit Toggling,
50% Duty Cycle
©1991 Fairchild Semiconductor Corporation
74ABT245 Rev. 1.5.0
www.fairchildsemi.com
4
74ABT245 — Octal Bi-Directional Transceiver with 3-STATE Outputs
DC Electrical Characteristics
SOIC package.
Symbol
V
OLP
V
OLV
V
OHV
V
IHD
V
ILD
Parameter
Quiet Output Maximum Dynamic V
OL
Quiet Output Minimum Dynamic V
OL
Minimum HIGH Level Dynamic
Output Voltage
Minimum HIGH Level Dynamic Input
Voltage
Maximum LOW Level Dynamic Input
Voltage
V
CC
5.0
5.0
5.0
5.0
5.0
Conditions
C
L
=
50 pF,
R
L
=
500Ω
T
A
=
25°C
(2)
T
A
=
25°C
(2)
T
A
=
25°C
(4)
T
A
=
25°C
(3)
T
A
=
25°C
(3)
Min.
–1.3
2.7
2.0
Typ.
0.7
–1.0
3.1
1.7
0.9
Max.
1.0
Units
V
V
V
V
0.6
V
Notes:
2. Max number of outputs defined as (n). n-1 data inputs are driven 0V to 3V. One output at LOW. Guaranteed, but not
tested.
3. Max number of data inputs (n) switching. n-1 inputs switching 0V to 3V. Input-under-test switching: 3V to threshold
(V
ILD
), 0V to threshold (V
IHD
). Guaranteed, but not tested.
4. Max number of outputs defined as (n). n – 1 data inputs are driven 0V to 3V. One output HIGH. Guaranteed, but not
tested.
AC Electrical Characteristics
SOIC and SSOP package.
T
A
=
+25°C,
V
CC
=
+5V,
C
L
=
50pF
Symbol
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
Output Disable Time
T
A
=
–55°C to +125°C,
V
CC
=
4.5V to 5.5V,
C
L
=
50pF
Min.
1.0
1.0
1.0
2.0
1.7
1.7
T
A
=
–40°C to +85°C,
V
CC
=
4.5V to 5.5V,
C
L
=
50pF
Min.
1.0
1.0
1.5
1.5
1.0
1.0
Parameter
Propagation Delay,
Data to Outputs
Output Enable Time
Min.
1.0
1.0
1.5
1.5
1.0
1.0
Typ.
2.1
2.4
3.2
3.7
3.6
3.3
Max.
3.6
3.6
6.0
6.0
6.1
5.6
Max.
4.8
4.8
6.7
7.5
7.4
6.5
Max.
3.6
3.6
6.0
6.0
6.1
5.6
Units
ns
ns
ns
©1991 Fairchild Semiconductor Corporation
74ABT245 Rev. 1.5.0
www.fairchildsemi.com
5
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