IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
EXTENDED COMMERCIAL 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)
– 1.27mm pitch SOIC, 0.65mm pitch SSOP,
0.635mm pitch QSOP, 0.65mm pitch TSSOP packages
– Extended commercial range of – 40°C to +85°C
– V
CC
= 3.3V ±0.3V, Normal Range
– V
CC
= 2.3V to 3.6V, Extended Range
– CMOS power levels (0.4µ W typ. static)
– Rail-to-Rail output swing for increased noise margin
– All inputs, outputs and I/O are 5 Volt tolerant
– Supports hot insertion
Drive Features for LVCH245A:
– High Output Drivers:
±24mA
– Reduced system switching noise
–
–
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.
APPLICATIONS:
• 5V and 3.3V mixed voltage systems
• Data communication and telecommunication systems
FUNCTIONAL BLOCK DIAGRAM
DIR
1
19
OE
A
1
2
18
B
1
TO SEVEN OTHER CHANNELS
EXTENDED COMMERCIAL TEMPERATURE RANGE
1
c
1999 Integrated Device Technology, Inc.
OCTOBER 1999
DSC-4611/-
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
EXTENDED COMMERCIAL TEMPERATURE RANGE
PIN CONFIGURATION
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
SO20-2
16
SO20-7
SO20-8
SO20-9
15
ABSOLUTE MAXIMUM RATINGS
V
CC
OE
B
1
B
2
B
3
B
4
B
5
B
6
B
7
B
8
Symbol
V
TERM(2)
V
TERM(3)
T
STG
I
OUT
I
IK
I
OK
I
CC
I
SS
Description
Terminal Voltage with Respect to GND
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
(1)
Unit
V
V
°C
mA
mA
mA
8LVC
Max.
– 0.5 to +6.5
– 0.5 to +6.5
– 65 to +150
– 50 to +50
– 50
±100
14
13
12
11
NOTES:
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.
2. V
CC
terminals.
3. All terminals except V
CC
.
SOIC/ SSOP/ QSOP/ TSSOP
TOP VIEW
CAPACITANCE
(T
A
= +25°C, f = 1.0MH
Z
)
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
8LVC Link
NOTE:
1. As applicable to the device type.
PIN DESCRIPTION
Pin Names
OE
Ax
Bx
DIR
Description
Output-enable Input (Active LOW)
Data Inputs
(1)
Data Outputs
Direction-control Input
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
B data to A bus
A data to B bus
High Z state
Operation
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don’t Care
Z = High-Impedance
2
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
EXTENDED COMMERCIAL 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
V
IL
I
IH
I
IL
I
OZH
I
OZL
I
OFF
V
IK
V
H
I
CCL
I
CCH
I
CCZ
∆I
CC
Parameter
Input HIGH Voltage Level
Input LOW Voltage Level
Input Leakage Current
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
3.6
≤
V
IN
≤
5.5V
(2)
Quiescent Power Supply
Current Variation
One input at V
CC
- 0.6V,
other inputs at V
CC
or GND
—
—
—
—
—
—
—
– 0.7
100
—
—
—
±50
– 1.2
—
10
10
500
µA
8LVC Link
Test Conditions
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
V
CC
= 3.6V
V
CC
= 3.6V
V
I
= 0 to 5.5V
V
O
= 0 to 5.5V
Min.
1.7
2
—
—
—
—
Typ.
(1)
—
—
—
—
—
—
Max.
—
—
0.7
0.8
±5
±10
Unit
V
V
µA
µA
µA
V
mV
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
8LVC Link
Parameter
(1)
Bus-Hold Input Sustain Current
Bus-Hold Input Sustain Current
Bus-Hold Input Overdrive Current
V
CC
= 3.0V
V
CC
= 2.3V
V
CC
= 3.6V
Test Conditions
V
I
= 2.0V
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
NOTES:
1. Pins with Bus-hold are identified in the pin description.
2. Typical values are at V
CC
= 3.3V, +25°C ambient.
3
IDT74LVCH245A
3.3V CMOS OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS
EXTENDED COMMERCIAL TEMPERATURE RANGE
OUTPUT DRIVE CHARACTERISTICS
Symbol
V
OH
Parameter
Output HIGH Voltage
V
CC
Test Conditions
(1)
= 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
I
OH
= – 24mA
I
OL
= 0.1mA
I
OL
= 6mA
I
OL
= 12mA
V
CC
= 2.7V
V
CC
= 3.0V
I
OL
= 12mA
I
OL
= 24mA
2.2
—
—
—
—
—
Max.
—
—
—
—
—
—
0.2
0.4
0.7
0.4
0.55
8LVC Link
Unit
V
V
CC
= 2.3V
V
CC
= 2.3V
V
CC
= 2.7V
V
CC
= 3.0V
V
CC
= 3.0V
V
OL
Output LOW Voltage
V
CC
= 2.3V to 3.6V
V
CC
= 2.3V
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, VCC = 3.3V
±
0.3V, TA = 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
pF
SWITCHING CHARACTERISTICS (1)
V
CC
= 2.5V±0.2V
Symbol
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
t
SK
(o)
Parameter
Propagation Delay
Ax or Bx to Bx or Ax
Output Enable Time
OE
to Ax or Bx
Output Disable Time
OE
to Ax or Bx
Output Skew
(2)
Min.
—
—
—
—
Max.
—
—
—
—
Min.
—
—
—
—
V
CC
= 2.7V
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
EXTENDED COMMERCIAL TEMPERATURE RANGE
TEST CONDITIONS
Symbol
V
LOAD
V
IH
V
T
V
LZ
V
HZ
C
L
V
CC
(1)
= 3.3V ±0.3V
6
2.7
1.5
300
300
50
6
2.7
1.5
300
300
50
TEST CIRCUITS AND WAVEFORMS
PROPAGATION DELAY
V
CC
(2)
= 2.5V ±0.2V Unit
2 x Vcc
V
Vcc
V
CC
/ 2
150
150
30
V
V
mV
mV
pF
8LVC Link
V
CC
(1)
= 2.7V
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
TEST CIRCUITS FOR ALL OUTPUTS
V
CC
500
Ω
Pulse
(1, 2)
Generator
V
IN
D.U.T.
500
Ω
C
L
V
OUT
V
LOAD
Open
GND
ENABLE AND DISABLE TIMES
ENABLE
CONTROL
INPUT
t
PZL
OUTPUT
SWITCH
NORMALLY
CLOSED
LOW
t
PZH
OUTPUT
SWITCH
NORMALLY
OPEN
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
R
T
LVC Link
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.
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
SET-UP, HOLD, AND RELEASE TIMES
DATA
INPUT
TIMING
INPUT
ASYNCHRONOUS
CONTROL
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
GND
Open
8LVC Link
OUTPUT SKEW - tsk (x)
INPUT
t
PLH1
t
PHL1
SYNCHRONOUS
CONTROL
t
SU
t
H
V
IH
V
T
0V
V
OH
PULSE WIDTH
LOW-HIGH-LOW
PULSE
t
W
HIGH-LOW-HIGH
PULSE
V
T
LVC Link
OUTPUT 1
t
SK
(x)
t
SK
(x)
V
T
V
OL
V
OH
V
T
OUTPUT 2
t
PLH2
t
PHL2
V
T
V
OL
t
SK
(x)
= t
PLH2
-
t
PLH1
or
t
PHL2
-
t
PHL1
LVC
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.
Link
5
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