MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
1
REV 3
Motorola, Inc. 1996
9/95
Low-Voltage CMOS Octal
Transceiver
With 5V-Tolerant Inputs and Outputs
(3-State, Non-Inverting)
The MC74LCX245 is a high performance, noninverting octal
transceiver operating from a 2.7 to 3.6V supply. High impedance TTL
compatible inputs significantly reduce current loading to input drivers
while TTL compatible outputs offer improved switching noise
performance. A VI specification of 5.5V allows MC74LCX245 inputs to be
safely driven from 5V devices. The MC74LCX245 is suitable for memory
address driving and all TTL level bus oriented transceiver applications.
Current drive capability is 24mA at both A and B ports. The
Transmit/Receive (T/R) input determines the direction of data flow
through the bidirectional transceiver. Transmit (activeHIGH) enables
data from A ports to B ports; Receive (activeLOW) enables data from B
to A ports. The Output Enable input, when HIGH, disables both A and B
ports by placing them in a HIGH Z condition.
Designed for 2.7 to 3.6V VCC Operation
5V Tolerant -- Interface Capability With 5V TTL Logic
Supports Live Insertion and Withdrawal
IOFF Specification Guarantees High Impedance When VCC = 0V
LVTTL Compatible
LVCMOS Compatible
24mA Balanced Output Sink and Source Capability
Near Zero Static Supply Current in All Three Logic States (10
A)
Substantially Reduces System Power Requirements
Latchup Performance Exceeds 500mA
ESD Performance: Human Body Model >2000V; Machine Model >200V
Pinout: 20Lead (Top View)
19
20
18
17
16
15
14
2
1
3
4
5
6
7
VCC
13
8
12
9
11
10
OE
B0
B1
B2
B3
B4
B5
B6
B7
T/R
A0
A1
A2
A3
A4
A5
A6
A7
GND
DW SUFFIX
PLASTIC SOIC
CASE 751D04
DT SUFFIX
PLASTIC TSSOP
CASE 948E02
20
1
20
1
M SUFFIX
PLASTIC SOIC EIAJ
CASE 96701
20
1
SD SUFFIX
PLASTIC SSOP
CASE 940C03
20
1
MC74LCX245
LOWVOLTAGE CMOS
OCTAL TRANSCEIVER
PIN NAMES
Function
Output Enable Input
Transmit/Receive Input
Side A 3State Inputs or 3State
Outputs
Side B 3State Inputs or 3State
Outputs
Pins
OE
T/R
A0A7
B0B7
MC74LCX245
MOTOROLA
LCX DATA
BR1339 -- REV 3
2
B0
OE 19
T/R 1
A0
B1
A1
B2
A2
B3
A3
B4
A4
B5
A5
B6
A6
B7
A7
LOGIC DIAGRAM
2
3
4
5
6
7
8
9
18
17
16
15
14
13
12
11
INPUTS
OPERATING MODE
OE
T/R
OPERATING MODE
NonInverting
L
L
B Data to A Bus
L
H
A Data to B Bus
H
X
Z
H = High Voltage Level; L = Low Voltage Level; Z = High Impedance State; X = High or Low Voltage Level
and Transitions are Acceptable; For ICC reasons, Do Not Float Inputs
MC74LCX245
LCX DATA
BR1339 -- REV 3
3
MOTOROLA
ABSOLUTE MAXIMUM RATINGS*
Symbol
Parameter
Value
Condition
Unit
VCC
DC Supply Voltage
0.5 to +7.0
V
VI
DC Input Voltage
0.5
VI
+7.0
V
VO
DC Output Voltage
0.5
VO
+7.0
Output in 3State
V
0.5
VO
VCC + 0.5
Note 1.
V
IIK
DC Input Diode Current
50
VI < GND
mA
IOK
DC Output Diode Current
50
VO < GND
mA
+50
VO > VCC
mA
IO
DC Output Source/Sink Current
50
mA
ICC
DC Supply Current Per Supply Pin
100
mA
IGND
DC Ground Current Per Ground Pin
100
mA
TSTG
Storage Temperature Range
65 to +150
C
* Absolute maximum continuous ratings are those values beyond which damage to the device may occur. Exposure to these conditions or conditions
beyond those indicated may adversely affect device reliability. Functional operation under absolutemaximumrated conditions is not implied.
1. Output in HIGH or LOW State. IO absolute maximum rating must be observed.
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Min
Typ
Max
Unit
VCC
Supply Voltage
Operating
Data Retention Only
2.0
1.5
3.3
3.3
3.6
3.6
V
VI
Input Voltage
0
5.5
V
VO
Output Voltage
(HIGH or LOW State)
(3State)
0
0
VCC
5.5
V
IOH
HIGH Level Output Current, VCC = 3.0V 3.6V
24
mA
IOL
LOW Level Output Current, VCC = 3.0V 3.6V
24
mA
IOH
HIGH Level Output Current, VCC = 2.7V 3.0V
12
mA
IOL
LOW Level Output Current, VCC = 2.7V 3.0V
12
mA
TA
Operating FreeAir Temperature
40
+85
C
t/
V
Input Transition Rise or Fall Rate, VIN from 0.8V to 2.0V,
VCC = 3.0V
0
10
ns/V
DC ELECTRICAL CHARACTERISTICS
TA = 40
C to +85
C
Symbol
Characteristic
Condition
Min
Max
Unit
VIH
HIGH Level Input Voltage (Note 2.)
2.7V
VCC
3.6V
2.0
V
VIL
LOW Level Input Voltage (Note 2.)
2.7V
VCC
3.6V
0.8
V
VOH
HIGH Level Output Voltage
2.7V
VCC
3.6V; IOH = 100
A
VCC 0.2
V
VCC = 2.7V; IOH = 12mA
2.2
VCC = 3.0V; IOH = 18mA
2.4
VCC = 3.0V; IOH = 24mA
2.2
VOL
LOW Level Output Voltage
2.7V
VCC
3.6V; IOL = 100
A
0.2
V
VCC = 2.7V; IOL= 12mA
0.4
VCC = 3.0V; IOL = 16mA
0.4
VCC = 3.0V; IOL = 24mA
0.55
2. These values of VI are used to test DC electrical characteristics only.
MC74LCX245
MOTOROLA
LCX DATA
BR1339 -- REV 3
4
DC ELECTRICAL CHARACTERISTICS
(continued)
TA = 40
C to +85
C
Symbol
Characteristic
Condition
Min
Max
Unit
II
Input Leakage Current
2.7V
VCC
3.6V; 0V
VI
5.5V
5.0
A
IOZ
3State Output Current
2.7
VCC
3.6V; 0V
VO
5.5V;
VI = VIH or V IL
5.0
A
IOFF
PowerOff Leakage Current
VCC = 0V; VI or VO = 5.5V
10
A
ICC
Quiescent Supply Current
2.7
VCC
3.6V; VI = GND or VCC
10
A
2.7
VCC
3.6V; 3.6
VI or VO
5.5V
10
A
ICC
Increase in ICC per Input
2.7
VCC
3.6V; VIH = VCC 0.6V
500
A
AC CHARACTERISTICS (tR = tF = 2.5ns; CL = 50pF; RL = 500
)
Limits
TA = 40
C to +85
C
VCC = 3.0V to 3.6V
VCC = 2.7V
Symbol
Parameter
Waveform
Min
Max
Max
Unit
tPLH
tPHL
Propagation Delay
Input to Output
1
1.5
1.5
7.0
7.0
8.0
8.0
ns
tPZH
tPZL
Output Enable Time to
High and Low Level
2
1.5
1.5
8.5
8.5
9.5
9.5
ns
tPHZ
tPLZ
Output Disable Time From
High and Low Level
2
1.5
1.5
7.5
7.5
8.5
8.5
ns
tOSHL
tOSLH
OutputtoOutput Skew
(Note 3.)
1.0
1.0
ns
3. Skew is defined as the absolute value of the difference between the actual propagation delay for any two separate outputs of the same device.
The specification applies to any outputs switching in the same direction, either HIGHtoLOW (tOSHL) or LOWtoHIGH (tOSLH); parameter
guaranteed by design.
DYNAMIC SWITCHING CHARACTERISTICS
TA = +25
C
Symbol
Characteristic
Condition
Min
Typ
Max
Unit
VOLP
Dynamic LOW Peak Voltage (Note 4.)
VCC = 3.3V, CL = 50pF, VIH = 3.3V, VIL = 0V
0.8
V
VOLV
Dynamic LOW Valley Voltage (Note 4.)
VCC = 3.3V, CL = 50pF, VIH = 3.3V, VIL = 0V
0.8
V
4. Number of outputs defined as "n". Measured with "n1" outputs switching from HIGHtoLOW or LOWtoHIGH. The remaining output is
measured in the LOW state.
CAPACITIVE CHARACTERISTICS
Symbol
Parameter
Condition
Typical
Unit
CIN
Input Capacitance
VCC = 3.3V, VI = 0V or VCC
7
pF
CI/O
Input/Output Capacitance
VCC = 3.3V, VI = 0V or VCC
8
pF
CPD
Power Dissipation Capacitance
10MHz, VCC = 3.3V, VI = 0V or VCC
25
pF
MC74LCX245
LCX DATA
BR1339 -- REV 3
5
MOTOROLA
WAVEFORM 1 PROPAGATION DELAYS
tR = tF = 2.5ns, 10% to 90%; f = 1MHz; tW = 500ns
2.7V
0V
VOH
VOL
An, Bn
Bn, An
tPHL
tPLH
WAVEFORM 2 OUTPUT ENABLE AND DISABLE TIMES
tR = tF = 2.5ns, 10% to 90%; f = 1MHz; tW = 500ns
2.7V
0V
0V
OE, T/R
An, Bn
tPZH
3.0V
tPHZ
tPZL
tPLZ
An, Bn
1.5V
1.5V
1.5V
1.5V
1.5V
1.5V
Figure 1. AC Waveforms
1.5V
VCC
VOH 0.3V
VOL + 0.3V
GND
1.5V
OPEN
PULSE
GENERATOR
RT
DUT
VCC
RL
R1
CL
6V
GND
TEST
SWITCH
tPLH, tPHL
Open
tPZL, tPLZ
6V
Open Collector/Drain tPLH and tPHL
6V
tPZH, tPHZ
GND
CL = 50pF or equivalent (Includes jig and probe capacitance)
RL = R1 = 500
or equivalent
RT = ZOUT of pulse generator (typically 50
)
Figure 2. Test Circuit
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