PI74LVC4245A
8-Bit Dual Supply Bus Transceiver
with 3-State Outputs
Product Features
• 4.5V to 5.5V on A-port and 2.7V to 3.6V on B-port
• Latch-up performance exceeds 200mA Per JESD78
• ESD protection exceeds JESD 22
– 2000V Human-Body Model (A114-B)
– 200V Machine Model (A115-A)
• Industrial Temperature: –40°C to +85°C
• Packaging (Pb-free & Green available):
– 24-pin 173-mil wide plastic TSSOP (L)
– 24-pin 150-mil wide plastic QSOP (Q)
– 24-pin 300-mil wide plastic SOIC (S)
Product Description
The PI74LVC4245A is a non-inverting 8-bit Bidirectional Trans-
ceiver that uses two separate power supply rails. A-port (V
CCA
)
is set to operate at 5V and B-port (V
CCB
) is set to operate at 3.3V.
This allows for translation from a 3.3V to a 5V environment and
vice-versa. This tranceiver is designed for asynchronous two-way
communication between data buses. The direction control input pin
(DIR) determines the dataflow from the A bus to the B bus or from
the B bus to the A bus. The output enable (OE) input, when HIGH,
disables both A and B ports by placing them in HIGH Z condi-
tion.
Logic Block Diagram
DIR
2
22
Product Pin Configuration
OE
(5V) V
CCA
DIR
A1
A2
A3
A4
A5
A6
A7
A8
GND
GND
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
VCCB (3.3V )
VCCB (3.3V )
OE
B1
B2
B3
B4
B5
B6
B7
B8
GND
A
1
3
A
2
4
21
B
1
20
B
2
19
18
17
16
A
3
5
A
4
6
B
3
A
5
7
B
4
A
6
8
B
5
A
7
9
B
6
A
8 10
15
B
7
14
B
8
Product Pin Description
Pin Name
OE
Description
3-State Output Enable Inputs (Active LOW)
Direction Control Input
Side A Inputs or 3-State Outputs
Side B Inputs or 3-State Outputs
Ground
Power
Truth Table
(1)
Inputs
OE
L
L
H
DIR
L
H
X
Bus B Data to Bus A
Bus A Data to Bus B
Z (Isolation)
L = Low Signal Level
Z = High Impedance
1
Outputs
DIR
Ax
Bx
GND
V
CCA
,V
CCB
Note:
1. H = High Signal Level
X = Don’t Care or Irrelevant
06-0211
PS8701B
06/05/06
PI74LVC4245A
8-Bit Dual Supply Bus Transceiver
with 3-State Outputs
Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
Supply voltage range, V
CCA
and V
CCB ............................
–0.5V to +7V
Input voltage range, V
I(1)
: I/O ports (A-port)
....
–0.5V to V
CCA
+0.5V
I/O ports (B-port)
...........
–0.5V to V
CCB
+0.5V
Control Pins
.................
–0.5V to V
CCA
+0.5V
Input clamp current, I
IK
(V
I
<0)................................................–50mA
Output clamp current, I
OK
(V
O
<0)...........................................–50mA
Continous Output Current I
O
..................................................±50mA
Continous Current through each VCC or GND pin .......................±100mA
Package thermal impedance, θ
JA(2)
: package L...................... 84°C/W
package Q...................... 98°C/W
package S ...................... 79°C/W
Storage Temperature range, T
stg
................................–65°C to 150°C
Notes:
Stresses greater than those listed under MAXIMUM RATINGS may cause
permanent damage to the device. This is a stress rating only and func-
tional operation of the device at these or any other conditions above those
indicated in the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for extended periods
may affect reliability.
1. This value is limited to 7V maximum.
2. The package thermal impedance is calculated in accordance with
JESD 51.
Recommended Operating Conditions for V
CCA
= 4.5V to 5.5V
(1)
Parameter
V
CCA
V
IH
V
IL
V
I
V
O
I
OH
I
OL
T
A
Supply Voltage
High-Level Input Voltage
Low-Level Input Voltage
Input Voltage
Output Voltage
High-Level Output Current
Low-Level Output Current
Operating Free-Air Temperature
–40
0
0
Description
Min.
4.5
2
0.8
V
CCA
V
CCA
–24
24
85
mA
°C
V
Max.
5.5
Units
Notes:
1. All unused inputs of the device must be held at the associated V
CC
or GND to ensure proper device operation.
Recommended Operating Conditions for V
CCB
= 2.7V to 3.6V
(1)
Parameter
V
CCB
V
IH
V
IL
V
I
V
O
I
OH
I
OL
T
A
Supply Voltage
High-Level Input Voltage
Low-Level Input Voltage
Input Voltage
Output Voltage
High-Level Output Current
Low-Level Output Current
Operating Free-Air Temperature
V
CCB
= 2.7V
V
CCB
= 3V
V
CCB
= 2.7V
V
CCB
= 3V
–40
V
CCB
= 2.7V to 3.6V
V
CCB
= 2.7V to 3.6V
0
0
Description
Min.
2.7
2
0.8
V
CCB
V
CCB
–12
–24
12
24
85
°C
mA
V
Max.
3.6
Units
Notes:
1. All unused inputs of the device must be held at the associated V
CC
or GND to ensure proper device operation.
06-0211
2
PS8701B
06/05/06
PI74LVC4245A
8-Bit Dual Supply Bus Transceiver
with 3-State Outputs
DC Electrical Characteristics
(Over Supply Voltage and Operating Temperature Ranges, unless otherwise specified)
A-Port (5V)
Param-
eters
Description
Test Conditions
I
OH
= –100µA
I
OH
= –24mA
I
OL
= 100µA
I
OL
= 24mA
V
I
= V
CCA
or GND
V
CCA
4.5V
5.5V
4.5V
5.5V
4.5V
5.5V
4.5V
5.5V
5.5V
V
CCB
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
0.19
0.19
Min.
4.4
5.4
3.7
4.7
Typ.
(1)
4.5
5.5
4.17
5.2
0.1
0.1
0.5
0.5
±1
µA
V
Max.
Units
V
OH
Minimum High Level
Output Voltage
V
OL
Maximum Low Level
Output Voltage
Maximum Input Leak-
age Current (Control
Inputs)
I
I
(2)
I
OZ
Maximum 3-State
Output Leakage Current V
O
= V
CCA
or GND
(A port)
Quiescent V
CCA
Supply V
I
= V
CCA
or GND,
Current
I
O
= 0
I
CCA
per input (A port
and Control Inputs)
One Input at 3.4V, other
inputs at V
CCA
or GND
5.5V
5.5V
5.5V
Open
5V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
2.7V to 3.6V
0.65
2.4
±5
10
1.5
I
CCA
∆ I
CCA(3)
C
I
C
IO
mA
Input Capacitance (Con-
V
I
= V
CCA
or GND
trol Inputs)
Input/Output Capaci-
tance (A port)
V
O
= V
CCA
or GND
pF
9.5
Notes:
5. All typical values are measured at V
CCA
= 5V, T
A
= 25°C
6. For I/O ports, the parameter I
OZ
includes the input leakage current.
7. This is the increase in supply current for each input that is at one of the specified voltage levels, rather than 0V or the associated V
CC
.
06-0211
3
PS8701B
06/05/06
PI74LVC4245A
8-Bit Dual Supply Bus Transceiver
with 3-State Outputs
DC Electrical Characteristics
(Over Supply Voltage and Operating Temperature Ranges, unless otherwise specified)
B-Port (3.3V)
Parameters Description
Minimum High
Level Output Volt-
age
Maximum Low
Level Output Volt-
age
Maximum 3-State
Output Leakage
Current (B port)
Quiescent V
CCB
Supply Current
I
CCB
per input
Input/Output Ca-
pacitance (B port)
Test Conditions
I
OH
= –100µA
I
OH
= –12mA
I
OH
= –24mA
I
OL
= 100µA
I
OL
= 12mA
I
OL
= 24mA
V
O
= V
CCB
or GND
V
I
= V
CCB
or GND,
I
O
= 0
One Input at V
CCB
–0.6V, other inputs
at V
CCB
or GND
V
O
= V
CCB
or GND
V
OL
V
CCA
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
V
CCB
2.7V to 3.6V
2.7V
3V
3V
2.7V to 3.6V
2.7V
3V
3.6V
3.6V
2.7V to 3.6V
3.3V
9.7
0.09
0.18
Min.
V
CC
–0.1
2.2
2.4
2
2.56
2.85
2.70
0.1
0.4
0.5
±5
10
50
pF
µA
V
Typ.
(1)
Max. Units
V
OH
I
OZ
(2)
I
CCB
∆I
CCB(3)
C
IO
Notes:
1. All typical values are measured at V
CCB
= 3.3V, T
A
= 25°C
2. For I/O ports, the parameter I
OZ
includes the input leakage current.
3. This is the increase in supply current for each input that is at one of the specified voltage levels, rather than 0V or the associated V
CC
.
Capacitance
(V
CCA
= 4.5V to 5.5V, V
CCB
= 2.7V to 3.6V, T
A
= 25°C)
Parameters
C
PD
Description
Power Dissipation Capaci-
tance
(1)
Test Conditions
Outputs Enabled
Outputs Disabled
C
L
= 0pF, f = 10 MHz
Typ.
20
2.3
Units
pF
Notes:
1. C
PD
is defined as the value of the internal equivalent capacitance which is derived from dynamic operating current consumption (I
CCD
) at no
output loading and operating at 50% duty cycle, C
PD
is related to I
CCD
dynamic operating current by the expression:
I
CCD =
(C
PD
)(V
CC
)(f
IN
) +(I
CC
static)
06-0211
4
PS8701B
06/05/06
PI74LVC4245A
8-Bit Dual Supply Bus Transceiver
with 3-State Outputs
AC Electrical Characteristics
Parameters
t
PHL
t
PLH
t
PHL
t
PLH
t
PZL
t
PZH
t
PZL
t
PZH
t
PLZ
t
PHZ
t
PLZ
t
PHZ
t
SK(O)
(Over Recommended Operating Free-Air Temperature Range unless otherwise noted, See Figure 1 and 2)
From
(Input)
A
B
OE
OE
OE
OE
Output-to-Output Skew
(1)
To
(Output)
B
A
A
B
A
B
V
CCA
=5V ± 0.5V,V
CCB
= 2.7V to 3.6V
C
L
= 50pF, R
L
= 500Ω
Min.
1
1
1
1
1
1
1
1
1
1
1
1
Max.
5.7
5.5
6.1
5.9
8
7.6
8
7.7
6.2
5.8
7
6.8
1.5
ns
Units
Notes:
1. Skew between any two outputs of the same device, switching in the same direction. Parameter guaranteed by design.
Power- Up Considerations
To avoid excessive supply current, bus contention or oscillation during power-up, the following guidelines should be followed:
1. Connect ground first before any supply voltage is applied.
2. Then Power up V
CCA
, which is the control side of the device.
3. Ramp OE ahead of or with V
CCA
to help prevent bus contention
4. Ramp DIR with V
CCA
if DIR HIGH is needed (A bus to B bus). Otherwise keep DIR LOW.
06-0211
5
PS8701B
06/05/06
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