IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
3.3V CMOS OCTAL BUS
TRANSCEIVER WITH 3-STATE
OUTPUTS, 5 VOLT TOLERANT I/O
AND BUS-HOLD
FEATURES:
• 0.5 MICRON CMOS Technology
• ESD > 2000V per MIL-STD-883, Method 3015; > 200V using
machine model (C = 200pF, R = 0)
• V
CC
= 3.3V ± 0.3V, Normal Range
• V
CC
= 2.7V to 3.6V, Extended Range
• CMOS power levels (0.4μ W typ. static)
μ
• Rail-to-rail output swing for increased noise margin
• All inputs, outputs, and I/O are 5V tolerant
• Supports hot insertion
• Available in SSOP, QSOP, and TSSOP packages
IDT74LVCH245A
DESCRIPTION:
The LVCH245A octal bus transceiver is built using advanced dual metal
CMOS technology. The device is designed for asynchronous communi-
cation between data buses. Data is transmitted 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 LVCH245A has been designed with a ±24mA output driver. This
driver is capable of driving a moderate to heavy load while maintaining
speed performance.
The LVCH245A has “bus-hold” which retains the inputs’ last state
whenever the input goes to a high-impedance. This prevents floating
inputs and eliminates the need for pull-up/down resistors.
Inputs can be driven from either 3.3V or 5V devices. This feature allows
the use of this device as a translator in a mixed 3.3V/5V system environ-
ment.
DRIVE FEATURES:
• High Output Drivers: ±24mA
• Reduced system switching noise
APPLICATIONS:
• 5V and 3.3V mixed voltage systems
• Data communication and telecommunication systems
FUNCTIONAL BLOCK DIAGRAM
DIR
1
19
2
18
OE
A
1
B
1
TO SEVEN OTHER CHANNELS
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
INDUSTRIAL TEMPERATURE RANGE
1
© 1999 Integrated Device Technology, Inc.
OCTOBER 1999
DSC-4611/3
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
TERM
T
STG
I
OUT
I
IK
I
OK
I
CC
I
SS
Description
Terminal Voltage with Respect to GND
Storage Temperature
DC Output Current
Continuous Clamp Current,
V
I
< 0 or V
O
< 0
Continuous Current through each
V
CC
or GND
Max
–0.5 to +6.5
–65 to +150
–50 to +50
–50
±100
Unit
V
°C
mA
mA
mA
DIR
A
1
A
2
A
3
A
4
A
5
A
6
A
7
A
8
GND
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
CC
OE
B
1
B
2
B
3
B
4
B
5
B
6
B
7
B
8
NOTE:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause
permanent damage to the device. This is a stress rating only and functional 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.
CAPACITANCE
(T
A
= +25°C, F = 1.0MHz)
Symbol
C
IN
C
OUT
C
I/O
Parameter
(1)
Input Capacitance
Output Capacitance
I/O Port Capacitance
Conditions
V
IN
= 0V
V
OUT
= 0V
V
IN
= 0V
Typ.
4.5
5.5
6.5
Max.
6
8
8
Unit
pF
pF
pF
SSOP/ QSOP/ TSSOP
TOP VIEW
NOTE:
1. As applicable to the device type.
PIN DESCRIPTION
Pin Names
OE
DIR
Ax
Bx
Description
Output Enable Input (Active LOW)
Direction Control Input
Data Inputs
(1)
Data Outputs
NOTE:
1. These pins have "Bus-Hold". All other pins are standard inputs, outputs, or I/Os.
FUNCTION TABLE
(1)
Inputs
OE
L
L
H
DIR
L
H
X
Outputs
Bus B Data to Bus A
Bus A Data to Bus B
Z
NOTES:
1. H = HIGH Voltage Level
X = Don’t Care
L = LOW Voltage Level
Z = High-Impedance
2
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Operating Condition: T
A
= –40°C to +85°C
Symbol
V
IH
Parameter
Input HIGH Voltage Level
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
V
IL
I
IH
I
IL
I
OZH
I
OZL
I
OFF
V
IK
V
H
I
CCL
I
CCH
I
CCZ
ΔI
CC
High Impedance Output Current
(3-State Output pins)
Input/Output Power Off Leakage
Clamp Diode Voltage
Input Hysteresis
Quiescent Power Supply Current
V
CC
= 0V, V
IN
or V
O
≤
5.5V
V
CC
= 2.3V, I
IN
= –18mA
V
CC
= 3.3V
V
CC
= 3.6V
V
IN
= GND or V
CC
—
—
—
—
—
—
—
–0.7
100
—
—
—
±50
–1.2
—
10
10
500
µA
V
mV
µA
V
CC
= 3.6V
V
O
= 0 to 5.5V
—
—
±10
µA
Input LOW Voltage Level
Input Leakage Current
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
V
CC
= 3.6V
V
I
= 0 to 5.5V
Test Conditions
Min.
1.7
2
—
—
—
Typ.
(1)
—
—
—
—
—
Max.
—
—
0.7
0.8
±5
µA
V
Unit
V
Quiescent Power Supply Current
Variation
3.6
≤
V
IN
≤
5.5V
(2)
One input at V
CC
- 0.6V, other inputs at V
CC
or GND
µA
NOTES:
1. Typical values are at V
CC
= 3.3V, +25°C ambient.
2. This applies in the disabled state only.
BUS-HOLD CHARACTERISTICS
Symbol
I
BHH
I
BHL
I
BHH
I
BHL
I
BHHO
I
BHLO
NOTES:
1. Pins with Bus-Hold are identified in the pin description.
2. Typical values are at V
CC
= 3.3V, +25°C ambient.
Parameter
(1)
Bus-Hold Input Sustain Current
Bus-Hold Input Sustain Current
Bus-Hold Input Overdrive Current
V
CC
= 3V
V
CC
= 2.3V
V
CC
= 3.6V
Test Conditions
V
I
= 2V
V
I
= 0.8V
V
I
= 1.7V
V
I
= 0.7V
V
I
= 0 to 3.6V
Min.
– 75
75
—
—
—
Typ.
(2)
—
—
—
—
—
Max.
—
—
—
—
±500
Unit
µA
µA
µA
3
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
OUTPUT DRIVE CHARACTERISTICS
Symbol
V
OH
Parameter
Output HIGH Voltage
V
CC
= 2.3V
V
CC
= 2.3V
V
CC
= 2.7V
V
CC
= 3V
V
CC
= 3V
V
OL
Output LOW Voltage
V
CC
= 2.3V to 3.6V
V
CC
= 2.3V
V
CC
= 2.7V
V
CC
= 3V
I
OH
= – 24mA
I
OL
= 0.1mA
I
OL
= 6mA
I
OL
= 12mA
I
OL
= 12mA
I
OL
= 24mA
Test Conditions
(1)
V
CC
= 2.3V to 3.6V
I
OH
= – 0.1mA
I
OH
= – 6mA
I
OH
= – 12mA
Min.
V
CC
– 0.2
2
1.7
2.2
2.4
2.2
—
—
—
—
—
Max.
—
—
—
—
—
—
0.2
0.4
0.7
0.4
0.55
V
Unit
V
NOTE:
1. V
IH
and V
IL
must be within the min. or max. range shown in the DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE table for the appropriate V
CC
range.
T
A
= – 40°C to + 85°C.
OPERATING CHARACTERISTICS, V
CC
= 3.3V ± 0.3V, T
A
= 25°C
Symbol
C
PD
C
PD
Parameter
Power Dissipation Capacitance per Transceiver Outputs enabled
Power Dissipation Capacitance per Transceiver Outputs disabled
Test Conditions
C
L
= 0pF, f = 10Mhz
Typical
47
2
Unit
pF
SWITCHING CHARACTERISTICS
(1)
V
CC
= 2.7V
Symbol
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
t
SK
(o)
Parameter
Propagation Delay
Ax to Bx, Bx to Ax
Output Enable Time
OE
to Ax or Bx
Output Disable Time
OE
to Ax or Bx
Output Skew
(2)
Min.
Max.
7.3
9.5
8.5
V
CC
= 3.3V ± 0.3V
Min.
1.5
1.5
1.7
Max.
6.3
8.5
7.5
1
Unit
ns
ns
ns
ns
—
—
—
—
—
—
NOTES:
1. See TEST CIRCUITS AND WAVEFORMS. T
A
= – 40°C to + 85°C.
2. Skew between any two outputs of the same package and switching in the same direction.
4
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
TEST CIRCUITS AND WAVEFORMS
TEST CONDITIONS
Symbol
V
LOAD
V
IH
V
T
V
LZ
V
HZ
C
L
V
CC(1)
= 3.3V±0.3V V
CC(1)
= 2.7V
6
2.7
1.5
300
300
50
6
2.7
1.5
300
300
50
V
CC(2)
= 2.5V±0.2V
2 x Vcc
Vcc
Vcc / 2
150
150
30
Unit
V
V
V
mV
mV
pF
SAME PHASE
INPUT TRANSITION
t
PLH
OUTPUT
t
PLH
OPPOSITE PHASE
INPUT TRANSITION
t
PHL
t
PHL
V
IH
V
T
0V
V
OH
V
T
V
OL
V
IH
V
T
0V
LVC Link
Propagation Delay
V
CC
500Ω
Pulse
(1, 2)
Generator
V
IN
D.U.T.
R
T
500Ω
C
L
LVC Link
V
LOAD
Open
GND
ENABLE
CONTROL
INPUT
t
PZL
OUTPUT
SWITCH
NORMALLY
V
LOAD
LOW
t
PZH
OUTPUT
SWITCH
NORMALLY
GND
HIGH
V
LOAD/2
V
T
t
PHZ
V
T
0V
t
PLZ
DISABLE
V
IH
V
T
0V
V
LOAD/2
V
OL+
V
LZ
V
OL
V
OH
V
OH-
V
HZ
0V
LVC Link
V
OUT
Test Circuit for All Outputs
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse Generator.
NOTES:
1. Pulse Generator for All Pulses: Rate
≤
10MHz; t
F
≤
2.5ns; t
R
≤
2.5ns.
2. Pulse Generator for All Pulses: Rate
≤
10MHz; t
F
≤
2ns; t
R
≤
2ns.
Enable and Disable Times
NOTE:
1. Diagram shown for input Control Enable-LOW and input Control Disable-HIGH.
SWITCH POSITION
Test
Open Drain
Disable Low
Enable Low
Disable High
Enable High
All Other Tests
Switch
V
LOAD
GND
Open
DATA
INPUT
TIMING
INPUT
ASYNCHRONOUS
CONTROL
SYNCHRONOUS
CONTROL
V
IH
V
T
0V
V
OH
V
T
V
OL
V
OH
V
T
V
OL
t
SU
t
H
t
REM
t
SU
t
H
V
IH
V
T
0V
V
IH
V
T
0V
V
IH
V
T
0V
V
IH
V
T
0V
LVC Link
INPUT
Set-up, Hold, and Release Times
t
PLH1
t
PHL1
OUTPUT 1
t
SK
(x)
t
SK
(x)
LOW-HIGH-LOW
PULSE
t
W
HIGH-LOW-HIGH
PULSE
V
T
OUTPUT 2
t
PLH2
t
PHL2
V
T
Pulse Width
LVC Link
LVC Link
t
SK
(x)
= t
PLH2
-
t
PLH1
or
t
PHL2
-
t
PHL1
Output Skew - t
SK
(
X
)
NOTES:
1. For t
SK
(o) OUTPUT1 and OUTPUT2 are any two outputs.
2. For t
SK
(b) OUTPUT1 and OUTPUT2 are in the same bank.
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