MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
Low-Voltage CMOS Octal
Transceiver
With 5V-Tolerant Inputs and Outputs
(3-State, Non-Inverting)
The MC74LCX245 is a high performance, non–inverting 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 bi–directional transceiver. Transmit (active–HIGH) enables
data from A ports to B ports; Receive (active–LOW) 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.
MC74LCX245
LOW–VOLTAGE CMOS
OCTAL TRANSCEIVER
20
1
DW SUFFIX
PLASTIC SOIC
CASE 751D–04
•
•
•
•
•
•
•
•
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 (10µA)
Substantially Reduces System Power Requirements
20
1
20
1
M SUFFIX
PLASTIC SOIC EIAJ
CASE 967–01
SD SUFFIX
PLASTIC SSOP
CASE 940C–03
•
Latchup Performance Exceeds 500mA
•
ESD Performance: Human Body Model >2000V; Machine Model >200V
20
1
DT SUFFIX
PLASTIC TSSOP
CASE 948E–02
Pinout: 20–Lead
(Top View)
VCC
20
OE
19
B0
18
B1
17
B2
16
B3
15
B4
14
B5
13
B6
12
B7
11
PIN NAMES
Pins
OE
T/R
A0–A7
B0–B7
Function
Output Enable Input
Transmit/Receive Input
Side A 3–State Inputs or 3–State
Outputs
Side B 3–State Inputs or 3–State
Outputs
1
T/R
2
A0
3
A1
4
A2
5
A3
6
A4
7
A5
8
A6
9
A7
10
GND
9/95
©
Motorola, Inc. 1996
1
REV 3
MC74LCX245
LOGIC DIAGRAM
OE 19
T/R 1
2
18
A1
3
17
A2
4
16
A3
5
15
A4
6
14
A5
7
13
A6
8
12
A7
9
11
A0
B0
B1
B2
B3
B4
B5
B6
B7
INPUTS
OE
L
L
H
T/R
L
H
X
OPERATING MODE
Non–Inverting
B Data to A Bus
A Data to B Bus
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
MOTOROLA
2
LCX DATA
BR1339 — REV 3
MC74LCX245
ABSOLUTE MAXIMUM RATINGS*
Symbol
VCC
VI
VO
Parameter
DC Supply Voltage
DC Input Voltage
DC Output Voltage
Value
–0.5 to +7.0
–0.5
≤
VI
≤
+7.0
–0.5
≤
VO
≤
+7.0
–0.5
≤
VO
≤
VCC + 0.5
IIK
IOK
DC Input Diode Current
DC Output Diode Current
–50
–50
+50
IO
ICC
IGND
TSTG
DC Output Source/Sink Current
DC Supply Current Per Supply Pin
DC Ground Current Per Ground Pin
Storage Temperature Range
±50
±100
±100
–65 to +150
Output in 3–State
Note 1.
VI < GND
VO < GND
VO > VCC
Condition
Unit
V
V
V
V
mA
mA
mA
mA
mA
mA
°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 absolute–maximum–rated conditions is not implied.
1. Output in HIGH or LOW State. IO absolute maximum rating must be observed.
RECOMMENDED OPERATING CONDITIONS
Symbol
VCC
VI
VO
IOH
IOL
IOH
IOL
TA
∆t/∆V
Supply Voltage
Input Voltage
Output Voltage
(HIGH or LOW State)
(3–State)
Parameter
Operating
Data Retention Only
Min
2.0
1.5
0
0
0
Typ
3.3
3.3
Max
3.6
3.6
5.5
VCC
5.5
–24
24
–12
12
–40
0
+85
10
Unit
V
V
V
mA
mA
mA
mA
°C
ns/V
HIGH Level Output Current, VCC = 3.0V – 3.6V
LOW Level Output Current, VCC = 3.0V – 3.6V
HIGH Level Output Current, VCC = 2.7V – 3.0V
LOW Level Output Current, VCC = 2.7V – 3.0V
Operating Free–Air Temperature
Input Transition Rise or Fall Rate, VIN from 0.8V to 2.0V,
VCC = 3.0V
DC ELECTRICAL CHARACTERISTICS
TA = –40°C to +85°C
Symbol
VIH
VIL
VOH
Characteristic
HIGH Level Input Voltage (Note 2.)
LOW Level Input Voltage (Note 2.)
HIGH Level Output Voltage
Condition
2.7V
≤
VCC
≤
3.6V
2.7V
≤
VCC
≤
3.6V
2.7V
≤
VCC
≤
3.6V; IOH = –100µA
VCC = 2.7V; IOH = –12mA
VCC = 3.0V; IOH = –18mA
VCC = 3.0V; IOH = –24mA
VOL
LOW Level Output Voltage
2.7V
≤
VCC
≤
3.6V; IOL = 100µA
VCC = 2.7V; IOL= 12mA
VCC = 3.0V; IOL = 16mA
VCC = 3.0V; IOL = 24mA
2. These values of VI are used to test DC electrical characteristics only.
VCC – 0.2
2.2
2.4
2.2
0.2
0.4
0.4
0.55
V
Min
2.0
0.8
Max
Unit
V
V
V
LCX DATA
BR1339 — REV 3
3
MOTOROLA
MC74LCX245
DC ELECTRICAL CHARACTERISTICS
(continued)
TA = –40°C to +85°C
Symbol
II
IOZ
IOFF
ICC
∆I
CC
Characteristic
Input Leakage Current
3–State Output Current
Power–Off Leakage Current
Quiescent Supply Current
Condition
2.7V
≤
VCC
≤
3.6V; 0V
≤
VI
≤
5.5V
2.7
≤
VCC
≤
3.6V; 0V
≤
VO
≤
5.5V;
VI = VIH or V IL
VCC = 0V; VI or VO = 5.5V
2.7
≤
VCC
≤
3.6V; VI = GND or VCC
2.7
≤
VCC
≤
3.6V; 3.6
≤
VI or VO
≤
5.5V
Increase in ICC per Input
2.7
≤
VCC
≤
3.6V; VIH = VCC – 0.6V
Min
Max
±5.0
±5.0
10
10
±10
500
Unit
µA
µA
µA
µA
µA
µA
AC CHARACTERISTICS
(tR = tF = 2.5ns; CL = 50pF; RL = 500Ω)
Limits
TA = –40°C to +85°C
VCC = 3.0V to 3.6V
Symbol
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
tOSHL
tOSLH
Propagation Delay
Input to Output
Output Enable Time to
High and Low Level
Output Disable Time From
High and Low Level
Output–to–Output Skew
(Note 3.)
Parameter
Waveform
1
2
2
Min
1.5
1.5
1.5
1.5
1.5
1.5
Max
7.0
7.0
8.5
8.5
7.5
7.5
1.0
1.0
VCC = 2.7V
Max
8.0
8.0
9.5
9.5
8.5
8.5
Unit
ns
ns
ns
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 HIGH–to–LOW (tOSHL) or LOW–to–HIGH (tOSLH); parameter
guaranteed by design.
DYNAMIC SWITCHING CHARACTERISTICS
TA = +25°C
Symbol
VOLP
VOLV
Characteristic
Dynamic LOW Peak Voltage (Note 4.)
Dynamic LOW Valley Voltage (Note 4.)
Condition
VCC = 3.3V, CL = 50pF, VIH = 3.3V, VIL = 0V
VCC = 3.3V, CL = 50pF, VIH = 3.3V, VIL = 0V
Min
Typ
0.8
0.8
Max
Unit
V
V
4. Number of outputs 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.
CAPACITIVE CHARACTERISTICS
Symbol
CIN
CI/O
CPD
Parameter
Input Capacitance
Input/Output Capacitance
Power Dissipation Capacitance
Condition
VCC = 3.3V, VI = 0V or VCC
VCC = 3.3V, VI = 0V or VCC
10MHz, VCC = 3.3V, VI = 0V or VCC
Typical
7
8
25
Unit
pF
pF
pF
MOTOROLA
4
LCX DATA
BR1339 — REV 3
MC74LCX245
2.7V
An, Bn
1.5V
1.5V
0V
tPLH
Bn, An
1.5V
tPHL
VOH
1.5V
VOL
WAVEFORM 1 – PROPAGATION DELAYS
tR = tF = 2.5ns, 10% to 90%; f = 1MHz; tW = 500ns
2.7V
OE, T/R
1.5V
1.5V
0V
tPZH
An, Bn
1.5V
≈
0V
tPZL
1.5V
VOL + 0.3V
GND
WAVEFORM 2 – OUTPUT ENABLE AND DISABLE TIMES
tR = tF = 2.5ns, 10% to 90%; f = 1MHz; tW = 500ns
tPLZ
≈
3.0V
tPHZ
VCC
VOH – 0.3V
An, Bn
Figure 1. AC Waveforms
VCC
6V
OPEN
GND
PULSE
GENERATOR
RT
DUT
CL
R1
RL
TEST
tPLH, tPHL
tPZL, tPLZ
Open Collector/Drain tPLH and tPHL
tPZH, tPHZ
SWITCH
Open
6V
6V
GND
CL = 50pF or equivalent (Includes jig and probe capacitance)
RL = R1 = 500Ω or equivalent
RT = ZOUT of pulse generator (typically 50Ω)
Figure 2. Test Circuit
LCX DATA
BR1339 — REV 3
5
MOTOROLA
京公网安备 11010802033920号
EEWORLD
