74LVC245A
LOW VOLTAGE CMOS OCTAL BUS TRANSCEIVER
(NOT INVERTED) HIGH PERFORMANCE
s
s
s
s
s
s
s
s
s
s
5V TOLERANT INPUTS
HIGH SPEED: t
PD
= 6.3ns (MAX.) at V
CC
= 3V
POWER DOWN PROTECTION ON INPUTS
AND OUTPUTS
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 24mA (MIN) at V
CC
= 3V
PCI BUS LEVELS GUARANTEED AT 24 mA
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 1.65V to 3.6V (1.2V Data
Retention)
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 245
LATCH-UP PERFORMANCE EXCEEDS
500mA (JESD 17)
ESD PERFORMANCE:
HBM > 2000V (MIL STD 883 method 3015);
MM > 200V
SOP
TSSOP
Table 1: Order Codes
PACKAGE
SOP
TSSOP
T&R
74LVC245AMTR
74LVC245ATTR
DESCRIPTION
The 74LVC245A is a low voltage CMOS OCTAL
BUS TRANSCEIVER (3-STATE) fabricated with
sub-micron silicon gate and double-layer metal
wiring C
2
MOS technology. It is ideal for 1.65 to 3.6
V
CC
operations and low power and low noise
applications.
This IC is intended for two-way asynchronous
communication between data buses and the
Figure 1: Pin Connection And IEC Logic Symbols
direction of data transmission is determined by
DIR input. The enable input G can be used to
disable the device so that the buses are effectively
isolated.
It has more speed performance at 3.3V than 5V
AC/ACT family, combined with a lower power
consumption.
All inputs are equipped with protection circuits
against static discharge, giving them 2KV ESD
immunity and transient excess voltage.
All floating bus terminals during High Z State must
be held HIGH or LOW.
July 2004
.
Rev. 4
1/12
74LVC245A
Figure 2: Input And Output Equivalent Circuit
Table 2: Pin Description
PIN N°
1
2, 3, 4, 5, 6,
7, 8, 9
18, 17, 16,
15, 14, 13,
12, 11
19
10
20
SYMBOL
DIR
A1 to A8
B1 to B8
NAME AND FUNCTION
Directional Control
Data Inputs/Outputs
Data Inputs/Outputs
Table 3: Truth Table
INPUTS
G
L
L
H
DIR
L
H
X
FUNCTION
A BUS
B BUS
OUTPUT
Yn
A=B
B=A
Z
OUTPUT
INPUT
INPUT
OUTPUT
Z
Z
G
GND
V
CC
Output Enable Input
Ground (0V)
Positive Supply Voltage
X : Don’t Care
Z : High Impedance
Table 4: Absolute Maximum Ratings
Symbol
V
CC
V
I
V
O
V
O
I
IK
I
OK
I
O
Supply Voltage
DC Input Voltage
DC Output Voltage (High Impedance or V
CC
= 0V)
DC Output Voltage (High or Low State) (note 1)
DC Input Diode Current
DC Output Diode Current (note 2)
DC Output Current
Parameter
Value
-0.5 to +7.0
-0.5 to +7.0
-0.5 to +7.0
-0.5 to V
CC
+ 0.5
- 50
- 50
±
50
±
100
-65 to +150
300
Unit
V
V
V
V
mA
mA
mA
mA
°C
°C
I
CC
or I
GND
DC V
CC
or Ground Current per Supply Pin
T
stg
Storage Temperature
T
L
Lead Temperature (10 sec)
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
1) I
O
absolute maximum rating must be observed
2) V
O
< GND
2/12
74LVC245A
Table 5: Recommended Operating Conditions
Symbol
V
CC
V
I
V
O
V
O
I
OH
, I
OL
I
OH
, I
OL
I
OH
, I
OL
I
OH
, I
OL
T
op
dt/dv
Supply Voltage (note 1)
Input Voltage
Output Voltage (High Impedance or V
CC
= 0V)
Output Voltage (High or Low State)
High or Low Level Output Current (V
CC
= 3.0 to 3.6V)
High or Low Level Output Current (V
CC
= 2.7 to 3.0V)
High or Low Level Output Current (V
CC
= 2.3 to 2.7V)
High or Low Level Output Current (V
CC
= 1.65 to 2.3V)
Operating Temperature
Input Rise and Fall Time (note 2)
Parameter
Value
1.65 to 3.6
0 to 5.5
0 to 5.5
0 to V
CC
±
24
±
12
±
8
±
4
-55 to 125
0 to 10
Unit
V
V
V
V
mA
mA
mA
mA
°C
ns/V
1) Truth Table guaranteed: 1.2V to 3.6V
2) V
IN
from 0.8V to 2V at V
CC
= 3.0V
Table 6: DC Specifications
Test Condition
Symbol
Parameter
V
CC
(V)
1.65 to 1.95
2.3 to 2.7
2.7 to 3.6
1.65 to 1.95
2.3 to 2.7
2.7 to 3.6
1.65 to 3.6
1.65
2.3
2.7
3.0
3.0
V
OL
Low Level Output
Voltage
1.65 to 3.6
1.65
2.3
2.7
3.0
I
I
I
off
I
OZ
Input Leakage Current
Power Off Leakage
Current
High Impedance
Output Leakage
Current
Quiescent Supply
Current
I
CC
incr. per Input
3.6
0
3.6
I
O
=-100
µA
I
O
=-4 mA
I
O
=-8 mA
I
O
=-12 mA
I
O
=-18 mA
I
O
=-24 mA
I
O
=100
µA
I
O
=4 mA
I
O
=8 mA
I
O
=12 mA
I
O
=24 mA
V
I
= 0 to 5.5V
V
I
or V
O
= 5.5V
V
I
= V
IH
orV
IL
V
O
= 0 to 5.5V
V
I
= V
CC
or GND
3.6
2.7 to 3.6
V
I
or V
O
= 3.6 to
5.5V
V
IH
= V
CC
-0.6V
V
CC
-0.2
1.2
1.7
2.2
2.4
2.2
0.2
0.45
0.7
0.4
0.55
±
5
10
±
10
-40 to 85 °C
Min.
0.65V
CC
1.7
2
0.35V
CC
0.7
0.8
V
CC
-0.2
1.2
1.7
2.2
2.4
2.2
0.2
0.45
0.7
0.4
0.55
±
5
10
±
10
µA
µA
µA
V
V
Max.
Value
-55 to 125 °C
Min.
0.65V
CC
1.7
2
0.35V
CC
0.7
0.8
V
V
Max.
Unit
V
IH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
V
IL
V
OH
I
CC
10
±
10
500
10
±
10
500
µA
µA
3/12
∆I
CC
74LVC245A
Table 7: Dynamic Switching Characteristics
Test Condition
Symbol
Parameter
V
CC
(V)
3.3
C
L
= 50pF
V
IL
= 0V, V
IH
= 3.3V
Value
T
A
= 25 °C
Min.
Typ.
0.8
-0.8
Max.
V
Unit
V
OLP
V
OLV
Dynamic Low Level Quiet
Output (note 1)
1) Number of output defined as "n". Measured with "n-1" outputs switching from HIGH to LOW or LOW to HIGH. The remaining output is
measured in the LOW state.
Table 8: AC Electrical Characteristics
Test Condition
Symbol
Parameter
V
CC
(V)
C
L
(pF)
30
30
50
50
30
30
50
50
30
30
50
50
R
L
(Ω)
1000
500
500
500
1000
500
500
500
1000
500
500
500
t
s
=
t
r
(ns)
2.0
2.0
2.5
2.5
2.0
2.0
2.5
2.5
2.0
2.0
2.5
2.5
-40 to 85 °C
Min.
2.0
2.0
1.5
1.0
2.0
2.0
1.0
1.0
2.0
2.0
2.0
2.0
Max.
9.0
8.0
7.3
6.3
12
9.5
9.0
8.5
11
9.0
8.5
7.5
1
Value
-55 to 125 °C
Min.
2.0
2.0
1.5
1.0
2.0
2.0
1.0
1.0
2.0
2.0
2.0
2.0
Max.
12
10.5
8.8
7.6
16
12.5
11
10
14
12
10
9.0
1
Unit
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
t
OSLH
t
OSHL
1.65 to 1.95
2.3 to 2.7
2.7
3.0 to 3.6
Output Enable Time 1.65 to 1.95
2.3 to 2.7
2.7
3.0 to 3.6
Output Disable Time 1.65 to 1.95
2.3 to 2.7
2.7
3.0 to 3.6
Output To Output
2.7 to 3.6
Skew Time (note1,
2)
Propagation Delay
Time
ns
ns
ns
ns
1) Skew is defined as the absolute value of the difference between the actual propagation delay for any two outputs of the same device switch-
ing in the same direction, either HIGH or LOW (t
OSLH
= | t
PLHm
- t
PLHn
|, t
OSHL
= | t
PHLm
- t
PHLn
|
2) Parameter guaranteed by design
Table 9: Capacitive Characteristics
Test Condition
Symbol
Parameter
V
CC
(V)
Value
T
A
= 25 °C
Min.
f
IN
= 10MHz
Typ.
4
1.8
2.5
3.3
28
30
34
Max.
pF
pF
Unit
C
IN
C
PD
Input Capacitance
Power Dissipation Capacitance
(note 1)
1) C
PD
is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
CC(opr)
= C
PD
x V
CC
x f
IN
+ I
CC
/n (per circuit)
4/12
74LVC245A
Figure 3: Test Circuit
R
T
= Z
OUT
of pulse generator (typically 50Ω)
Table 10: Test Circuit And Waveform Symbol Value
Symbol
1.65 to 1.95V
C
L
R
L
= R
1
V
S
V
IH
V
M
V
OH
V
X
V
Y
t
r
= t
r
30pF
1000Ω
2 x V
CC
V
CC
V
CC
/2
V
CC
V
OL
+ 0.15V
V
OH
- 0.15V
<2.0ns
2.3 to 2.7V
30pF
500Ω
2 x V
CC
V
CC
V
CC
/2
V
CC
V
OL
+ 0.15V
V
OH
- 0.15V
<2.0ns
V
CC
2.7V
50pF
500Ω
6V
2.7V
1.5V
3.0V
V
OL
+ 0.3V
V
OH
- 0.3V
<2.5ns
3.0 to 3.6V
50pF
500Ω
6V
2.7V
1.5V
3.0V
V
OL
+ 0.3V
V
OH
- 0.3V
<2.5ns
Figure 4: Waveform - Propagation Delays
(f=1MHz; 50% duty cycle)
5/12
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