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SN74LVC245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS218C – JANUARY 1993 – REVISED JULY 1994
•
•
•
•
EPIC
™
(Enhanced-Performance Implanted
CMOS) Submicron Process
Typical V
OLP
(Output Ground Bounce)
< 0.8 V at V
CC
= 3.3 V, T
A
= 25°C
Typical V
OHV
(Output V
OH
Undershoot)
> 2 V at V
CC
= 3.3 V, T
A
= 25°C
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages
DB, DW, OR PW PACKAGE
(TOP VIEW)
description
This octal bus transceiver is designed for 2.7-V to
3.6-V V
CC
operation.
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
The SN74LVC245 is designed for asynchronous communication between data buses. The device transmits
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 SN74LVC245 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
logic symbol
†
OE
DIR
19
1
G3
3EN1[BA]
3EN2[AB]
1
2
18
B1
logic diagram (positive logic)
DIR
1
19
OE
A1
2
A1
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
To Seven Other Channels
18
B1
† This symbol is in accordance with ANSI/IEEE Std 91-1984 and
IEC Publication 617-12.
EPIC 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
1
SN74LVC245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS218C – JANUARY 1993 – REVISED JULY 1994
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
†
Supply voltage range, V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.5 V to 4.6 V
Input voltage range, V
I
: except I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.5 V to 4.6 V
I/O ports (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.5 V to V
CC
+ 0.5 V
Output voltage range, V
O
(see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.5 V to V
CC
+ 0.5 V
Input clamp current, I
IK
(V
I
< 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 50 mA
Output clamp current, I
OK
(V
O
< 0 or V
O
> V
CC
) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±
50 mA
Continuous output current, I
O
(V
O
= 0 to V
CC
) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±
50 mA
Continuous current through V
CC
or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±
100 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
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. This value is limited to 4.6 V maximum.
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# SCBD002B.
recommended operating conditions (see Note 3)
MIN
VCC
VIH
VIL
VI
VO
IOH
IOL
∆t
/∆v
Supply voltage
High-level input voltage
Low-level input voltage
Input voltage
Output voltage
High-level
High level output current
Low-level
Low level output current
Input transition rise or fall rate
VCC = 2.7 V
VCC = 3 V
VCC = 2.7 V
VCC = 3 V
0
– 40
VCC = 2.7 V to 3.6 V
VCC = 2.7 V to 3.6 V
2.7
2
0.8
0
0
VCC
VCC
– 12
– 24
12
24
10
85
MAX
3.6
UNIT
V
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.
2
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN74LVC245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS218C – JANUARY 1993 – REVISED JULY 1994
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
IOH = – 100
µA
VOH
IOH = – 12 mA
IOH = – 24 mA
IOL = 100
µA
VOL
II
IOZ‡
ICC
IOL = 12 mA
IOL = 24 mA
VI = VCC or GND
VO = VCC or GND
VI = VCC or GND,
IO = 0
VCC = 3 V to 3.6 V,
One input at VCC – 0.6 V,
Other inputs at VCC or GND
Control inputs
VI = VCC or GND
VO = VCC or GND
TEST CONDITIONS
VCC†
MIN to MAX
2.7 V
3V
3V
MIN to MAX
2.7 V
3V
3.6 V
3.6 V
3.6 V
TA = – 40°C to 85°C
MIN
TYP
MAX
VCC – 0.2
2.2
2.4
2
0.2
0.4
0.55
±
5
±
10
20
500
3.3 V
5.5
6.7
µA
µA
µA
µA
pF
pF
V
UNIT
V
n
ICC
Ci
Cio
A or B ports
3.3 V
† For conditions shown as MIN or MAX, use the appropriate values under recommended operating conditions.
‡ For I/O ports, the parameter IOZ includes the input leakage current.
switching characteristics over recommended operating free-air temperature range, C
L
= 50 pF
(unless otherwise noted) (see Figure 1)
PARAMETER
tpd
ten
tdis
FROM
(INPUT)
A or B
OE
OE
TO
(OUTPUT)
B or A
A or B
A or B
VCC = 3.3 V
±
0.3 V
MIN TYP§
MAX
1.5
1.5
1.5
4
4.5
5.5
7
9
8
VCC = 2.7 V
MIN
MAX
8
10
9
UNIT
ns
ns
ns
§ All typical values are VCC = 3.3 V, TA = 25°C.
operating characteristics, V
CC
= 3.3 V, T
A
= 25°C
PARAMETER
Cpd
d
Power dissipation capacitance per transceiver
Outputs enabled
Outputs disabled
TEST CONDITIONS
CL = 50 pF
pF,
f = 10 MHz
TYP
25
2
UNIT
pF
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
3
SN74LVC245
OCTAL BUS TRANSCEIVER
WITH 3-STATE OUTPUTS
SCAS218C – JANUARY 1993 – REVISED JULY 1994
PARAMETER MEASUREMENT INFORMATION
6V
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
6V
GND
LOAD CIRCUIT FOR OUTPUTS
2.7 V
Timing Input
tw
2.7 V
Input
1.5 V
1.5 V
0V
VOLTAGE WAVEFORMS
PULSE DURATION
Data Input
tsu
1.5 V
th
2.7 V
1.5 V
0V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
2.7 V
1.5 V
tPZL
Output
Waveform 1
S1 at 6 V
(see Note C)
Output
Waveform 2
S1 at GND
(see Note C)
tPZH
tPLZ
1.5 V
tPHZ
VOH – 0.3 V
VOH
3V
VOL + 0.3 V
VOL
1.5 V
0V
1.5 V
0V
Input
(see Note B)
tPLH
Output
2.7 V
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
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
4
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•
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