IDT54/74FCT245T/AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
FAST CMOS OCTAL
BIDIRECTIONAL
TRANSCEIVER
FEATURES:
•
•
•
•
Std., A, and C grades
Low input and output leakage
≤
1µA (max.)
CMOS power levels
True TTL input and output compatibility:
– V
OH
= 3.3V (typ.)
– V
OL
= 0.3V (typ.)
High Drive outputs (-15mA I
OH
, 64mA I
OL
)
Meets or exceeds JEDEC standard 18 specifications
Military product compliant to MIL-STD-883, Class B and DESC
listed (dual marked)
Power off disable outputs permit "live insertion"
Available in the following packages:
– Industrial: SOIC, SSOP, QSOP, TSSOP
– Military: CERDIP, LCC
IDT54/74FCT245T/AT/CT
DESCRIPTION:
The IDT octal bidirectional transceivers are built using an advanced dual
metal CMOS technology. The FCT245T is designed for asynchronous two-
way communication between data buses. The transmit/receive (T/R) input
determines the direction of data flow through the bidirectional transceiver.
Transmit (active high) enables data from A ports to B ports, and receive
(active low) from B ports to A ports. The output enable (OE) input, when
high, disables both A and B ports by placing them in high Z condition.
•
•
•
•
•
FUNCTIONAL BLOCK DIAGRAM
T/
R
OE
A
0
B
0
A
1
B
1
A
2
B
2
A
3
B
3
A
4
B
4
A
5
B
5
A
6
B
6
A
7
B
7
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
1
OCTOBER 2008
DSC-5510/5
© 2006 Integrated Device Technology, Inc.
IDT54/74FCT245T/AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
PIN CONFIGURATION
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
GND
2
3
4
5
6
7
8
9
10
19
18
17
16
15
14
13
12
11
OE
B
0
B
1
B
2
B
3
B
4
B
5
B
6
B
7
3
2
1
20
19
18
17
16
15
14
9
10
11
12
13
A
2
A
3
A
4
A
5
A
6
T/R
A
1
OE
A
0
T/R
1
20
V
CC
INDEX
V
CC
4
5
6
7
8
B
0
B
1
B
2
B
3
B
4
GND
A
7
B
7
B
6
CERDIP/ SOIC/ SSOP/ QSOP/ TSSOP
TOP VIEW
LCC
TOP VIEW
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
TERM
(3)
T
STG
I
OUT
Description
Terminal Voltage with Respect to GND
Storage Temperature
DC Output Current
Max
–0.5 to +7
–0.5 to V
CC
+0.5
–65 to +150
–60 to +120
Unit
V
V
°C
mA
V
TERM
(2)
Terminal Voltage with Respect to GND
PIN DESCRIPTION
Pin Names
OE
T/R
A
0
- A
7
B
0
- B
7
Description
Output Enable Inputs (Active LOW)
Transmit/Recieve Input
Side A Inputs or 3-State Outputs
Side B Inputs or 3-State Outputs
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. No terminal voltage may exceed
Vcc by +0.5V unless otherwise noted.
2. Inputs and Vcc terminals only.
3. Output and I/O terminals only.
FUNCTION TABLE
(1)
Inputs
OE
L
L
H
T/R
L
H
X
Outputs
Bus B Data to Bus A
Bus A Data to Bus B
High Z State
CAPACITANCE
(T
A
= +25°C, F = 1.0MHz)
Symbol
C
IN
C
OUT
Parameter
(1)
Input Capacitance
Output Capacitance
Conditions
V
IN
= 0V
V
OUT
= 0V
Typ.
6
8
Max.
10
12
Unit
pF
pF
NOTE:
1. H = HIGH Voltage Level
X = Don’t Care
L = LOW Voltage Level
Z = High Impedance
NOTE:
1. This parameter is measured at characterization but not tested.
2
B
5
IDT54/74FCT245T/AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= –40°C to +85°C, V
CC
= 5.0V ±5%; Military: T
A
= –55°C to +125°C, V
CC
= 5.0V ±10%
Symbol
V
IH
V
IL
I
IH
I
IL
I
OZH
I
OZL
I
I
V
IK
V
H
I
CC
Parameter
Input HIGH Level
Input LOW Level
Input HIGH Current
(4)
Input LOW Current
(4)
High Impedance Output Current
(3-State output pins)
(4)
Input HIGH Current
(4)
Clamp Diode Voltage
Input Hysteresis
Quiescent Power Supply Current
V
CC
= Max., V
I
= V
CC
(Max.)
V
CC
= Min, I
IN
= -18mA
—
V
CC
= Max., V
IN
= GND or V
CC
Test Conditions
(1)
Guaranteed Logic HIGH Level
Guaranteed Logic LOW Level
V
CC
= Max.
V
CC
= Max.
V
CC
= Max
V
I
= 2.7V
V
I
= 0.5V
V
O
= 2.7V
V
O
= 0.5V
Min.
2
—
—
—
—
—
—
—
—
—
Typ.
(2)
—
—
—
—
—
—
—
–0.7
200
0.01
Max.
—
0.8
±1
±1
±1
±1
±1
–1.2
—
1
µA
V
mV
mA
Unit
V
V
µA
µA
µA
OUTPUT DRIVE CHARACTERISTICS
Symbol
V
OH
Parameter
Output HIGH Voltage
Test Conditions
(1)
V
CC
= Min
I
OH
= –6mA MIL
I
OH
= –8mA IND
V
IN
= V
IH
or V
IL
I
OH
= –12mA MIL
I
OH
= –15mA IND
V
CC
= Min
I
OL
= 48mA MIL
V
IN
= V
IH
or V
IL
I
OL
= 64mA IND
V
CC
= Max., V
O
= GND
(3)
Min.
2.4
2
—
–60
Typ.
(2)
3.3
3
0.3
–120
Max.
—
—
0.55
–225
V
mA
Unit
V
V
OL
I
OS
Output LOW Voltage
Short Circuit Current
NOTES:
1. For conditions shown as Min. or Max., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 5.0V, +25°C ambient.
3. Not more than one output should be tested at one time. Duration of the test should not exceed one second.
4. The test limit for this parameter is ±5µA at T
A
= –55°C.
3
IDT54/74FCT245T/AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
POWER SUPPLY CHARACTERISTICS
Symbol
ΔI
CC
I
CCD
Parameter
Quiescent Power Supply Current
TTL Inputs HIGH
Dynamic Power Supply
Current
(4)
V
CC
= Max.
V
IN
= 3.4V
(3)
V
CC
= Max.
Outputs Open
OE
= T/R = GND
One Input Toggling
50% Duty Cycle
V
CC
= Max.
Outputs Open
fi = 10MHz
50% Duty Cycle
OE
= T/R = GND
One Bit Toggling
V
CC
= Max.
Outputs Open
fi = 2.5MHz
50% Duty Cycle
OE
= T/R = GND
Eight Bits Toggling
V
IN
= V
CC
V
IN
= GND
Test Conditions
(1)
Min.
—
—
Typ.
(2)
0.5
0.15
Max.
2
0.25
Unit
mA
mA/
MHz
I
C
Total Power Supply Current
(6)
V
IN
= V
CC
V
IN
= GND
V
IN
= 3.4V
V
IN
= GND
V
IN
= V
CC
V
IN
= GND
V
IN
= 3.4V
V
IN
= GND
—
1.5
3.5
mA
—
1.8
4.5
—
3
6
(5)
—
5
14
(5)
NOTES:
1. For conditions shown as Min. or Max., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 5.0V, +25°C ambient.
3. Per TTL driven input; (V
IN
= 3.4V). All other inputs at V
CC
or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. Values for these conditions are examples of
ΔI
CC
formula. These limits are guaranteed but not tested.
6. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
ΔI
CC
D
H
N
T
+ I
CCD
(f
CP
/2+ f
i
N
i
)
I
CC
= Quiescent Current
ΔI
CC
= Power Supply Current for a TTL High Input (V
IN
= 3.4V)
D
H
= Duty Cycle for TTL Inputs High
N
T
= Number of TTL Inputs at D
H
I
CCD
= Dynamic Current caused by an Input Transition Pair (HLH or LHL)
f
CP
= Clock Frequency for Register Devices (Zero for Non-Register Devices)
f
i
= Output Frequency
N
i
= Number of Outputs at f
i
All currents are in milliamps and all frequencies are in megahertz.
4
IDT54/74FCT245T/AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
SWITCHING CHARACTERISTICS OVER OPERATING RANGE - INDUSTRIAL
Symbol
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
t
PZH
t
PZL
t
PHZ
t
PLZ
Parameter
Propagation Delay
A to B, B to A
Output Enable Time
OE
to A or B
Output Disable Time
OE
to A or B
Output Enable Time
T/R to A or B
(3)
Output Disable Time
T/R to A or B
(3)
Condition
(1)
C
L
= 50pF
R
L
= 500Ω
74FCT245AT
Min.
(2)
Max.
1.5
4.6
1.5
1.5
1.5
1.5
6.2
5
6.2
5
74FCT245CT
Min.
(2)
Max.
1.5
4.1
1.5
1.5
1.5
1.5
5.8
4.8
5.8
4.8
Unit
ns
ns
ns
ns
ns
SWITCHING CHARACTERISTICS OVER OPERATING RANGE - MILITARY
Symbol
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
t
PZH
t
PZL
t
PHZ
t
PLZ
Parameter
Propagation Delay
A to B, B to A
Output Enable Time
OE
to A or B
Output Disable Time
OE
to A or B
Output Enable Time
T/R to A or B
(3)
Output Disable Time
T/R to A or B
(3)
Condition
(1)
C
L
= 50pF
R
L
= 500Ω
54FCT245T
Min.
(2)
Max.
1.5
7.5
1.5
1.5
1.5
1.5
10
10
10
10
54FCT245AT
Min.
(2)
Max.
1.5
4.9
1.5
1.5
1.5
1.5
6.5
6
6.5
6
54FCT245CT
Min.
(2)
Max.
1.5
4.5
1.5
1.5
1.5
1.5
6.2
5.2
6.2
5.2
Unit
ns
ns
ns
ns
ns
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
3. This parameter is guaranteed but not tested.
5
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