INDUSTRIAL TEMPERATURE RANGE
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
1
JUNE 2002
INDUSTRIAL TEMPERATURE RANGE
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
2002 Integrated Device Technology, Inc.
DSC-5511/2
FEATURES:
A and C grades
Low input and output leakage
1A (max.)
CMOS power levels
True TTL input and output compatibility:
V
OH
= 3.3V (typ.)
V
OL
= 0.3V (typ.)
Meets or exceeds JEDEC standard 18 specifications
Resistor outputs -15mA I
OH
, 12mA I
OL
Reduced system switching noise
Available in SOIC, QSOP, and TSSOP packages
FUNCTIONAL BLOCK DIAGRAM
IDT74FCT2245AT/CT
FAST CMOS OCTAL
BIDIRECTIONAL
TRANSCEIVER
DESCRIPTION:
The IDT octal bidirectional transceivers are built using an advanced dual
metal CMOS technology. The FCT2245T 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 trans-
ceiver. 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.
The FCT2245T has balanced drive outputs with current limiting resistors.
This offers low ground bounce, minimal undershoot and controlled output
fall times- reducing the need for external series terminating resistors. The
FCT2245T parts are plug-in replacements for FCT245T parts.
A
B
0
0
T/
R
O E
A
B
1
1
A
B
2
2
A
B
3
3
A
B
4
4
A
B
5
5
A
B
6
6
A
B
7
7
INDUSTRIAL TEMPERATURE RANGE
2
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
PIN CONFIGURATION
Pin Names
Description
OE
Output Enable Input (Active LOW)
T/R
Transmit/Receive Input
A
0
- A
7
Side A Inputs or 3-State Outputs
B
0
- B
7
Side BInputs or 3-State Outputs
PIN DESCRIPTION
NOTE:
1. H = HIGH Voltage Level
X = Don't Care
L = LOW Voltage Level
2
3
1
16
15
14
11
19
18
20
17
13
12
5
6
7
4
8
9
10
A
2
A
0
A
1
V
CC
A
3
A
6
A
4
A
5
A
7
GND
OE
B
2
B
0
B
1
B
3
B
6
B
4
B
5
B
7
T/R
SOIC/ QSOP/ TSSOP
TOP VIEW
FUNCTION TABLE
(1)
Inputs
OE
T/R
Outputs
L
L
Bus B Data to Bus A
L
H
Bus A Data to Bus B
H
X
High Z State
Symbol
Description
Max
Unit
V
TERM
(2)
Terminal Voltage with Respect to GND
0.5 to +7
V
V
TERM
(3)
Terminal Voltage with Respect to GND
0.5 to V
CC
+0.5
V
T
STG
Storage Temperature
65 to +150
C
I
OUT
DC Output Current
60 to +120
mA
ABSOLUTE MAXIMUM RATINGS
(1)
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.
Symbol
Parameter
(1)
Conditions
Typ.
Max.
Unit
C
IN
Input Capacitance
V
IN
= 0V
6
10
pF
C
OUT
Output Capacitance
V
OUT
= 0V
8
12
pF
CAPACITANCE
(T
A
= +25C, F = 1.0MHz)
NOTE:
1. This parameter is measured at characterization but not tested.
INDUSTRIAL TEMPERATURE RANGE
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
3
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
V
IH
Input HIGH Level
Guaranteed Logic HIGH Level
2
--
--
V
V
IL
Input LOW Level
Guaranteed Logic LOW Level
--
--
0.8
V
I
IH
Input HIGH Current
(4)
V
CC
= Max.
V
I
= 2.7V
--
--
1
A
I
IL
Input LOW Current
(4)
V
CC
= Max.
V
I
= 0.5V
--
--
1
A
I
OZH
High Impedance Output Current
V
CC
= Max.
V
I
= 2.7V
--
--
1
A
I
OZL
(3-State Output Pins)
(4)
V
I
= 0.5V
--
--
1
I
I
Input HIGH Current
(4)
V
CC
= Max., V
I
= V
CC
(Max.)
--
--
1
A
V
IK
Clamp Diode Voltage
V
CC
= Min., I
IN
= 18mA
--
0.7
1.2
V
V
H
Input Hysteresis
--
--
200
--
mV
I
CC
Quiescent Power Supply Current
V
CC
= Max.
--
0.01
1
mA
V
IN
= GND or V
CC
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= 40C to +85C, V
CC
= 5.0V 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, +25C 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 5
A at TA = -55C.
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
ODL
Output LOW Current
V
CC
= 5V, V
IN
= V
IH
or V
IL
, V
OUT
= 1.5V
(3)
16
48
--
mA
I
ODH
Output HIGH Current
V
CC
= 5V, V
IN
= V
IH
or V
IL
, V
OUT
= 1.5V
(3)
-16
-48
--
mA
V
OH
Output HIGH Voltage
V
CC
= Min
I
OH
= 15mA
2.4
3.3
--
V
V
IN
= V
IH
or V
IL
V
OL
Output LOW Voltage
V
CC
= Min
I
OL
= 12mA
--
0.3
0.5
V
V
IN
= V
IH
or V
IL
OUTPUT DRIVE CHARACTERISTICS
INDUSTRIAL TEMPERATURE RANGE
4
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
CC
Quiescent Power Supply Current
V
CC
= Max.
--
0.5
2
mA
TTL Inputs HIGH
V
IN
= 3.4V
(3)
I
CCD
Dynamic Power Supply
V
CC
= Max.
V
IN
= V
CC
--
0.06
0.12
mA/
Current
(4)
Outputs Open
V
IN
= GND
MHz
OE = T/R = GND
One Input Toggling
50% Duty Cycle
I
C
Total Power Supply Current
(6)
V
CC
= Max.
V
IN
= V
CC
--
0.6
2.2
mA
Outputs Open
V
IN
= GND
fi = 10MHz
50% Duty Cycle
V
IN
= 3.4V
--
0.9
3.2
OE = T/R = GND
V
IN
= GND
One BitToggling
V
CC
= Max.
V
IN
= V
CC
--
1.2
3.4
(5)
Outputs Open
V
IN
= GND
fi = 2.5MHz
50% Duty Cycle
V
IN
= 3.4V
--
3.2
11.4
(5)
OE = T/R = GND
V
IN
= GND
Eight Bits Toggling
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, +25C 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
I
CC
formula. These limits are guaranteed but not tested.
6. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
I
CC
D
H
N
T
+ I
CCD
(f
CP
/2+ f
i
N
i
)
I
CC
= Quiescent Current
I
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.
POWER SUPPLY CHARACTERISTICS
INDUSTRIAL TEMPERATURE RANGE
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
5
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.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
(1)
74FCT2245AT
74FCT2245CT
Symbol
Parameter
Condition
(1)
Min
.
(2)
Max.
Min
.
(2)
Max.
Unit
t
PLH
Propagation Delay
C
L
= 50 pF
1.5
4.6
1.5
4.1
ns
t
PHL
A to B, B to A
R
L
= 500
t
PZH
Output Enable Time
1.5
6.2
1.5
5.8
ns
t
PZL
OE to A or B
t
PHZ
Output Disable Time
1.5
5
1.5
4.8
ns
t
PLZ
OE to A or B
t
PZH
Output Enable Time
1.5
6.2
1.5
5.8
ns
t
PZL
T/R to A or B
(3)
t
PHZ
Output Disable Time
1.5
5
1.5
4.8
ns
t
PLZ
T/R to A or B
(3)
INDUSTRIAL TEMPERATURE RANGE
6
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
Pulse
Generator
R
T
D.U.T
.
V
CC
V
IN
C
L
V
OUT
50pF
500
500
7.0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
DATA
INPUT
TIMING
INPUT
ASYNCHRONOUS CONTROL
PRESET
CLEAR
ETC.
SYNCHRONOUS CONTROL
t
SU
t
H
t
REM
t
SU
t
H
HIGH-LOW-HIGH
PULSE
LOW-HIGH-LOW
PULSE
t
W
1.5V
1.5V
SAME PHASE
INPUT TRANSITION
3V
1.5V
0V
1.5V
V
OH
t
PLH
OUTPUT
OPPOSITE PHASE
INPUT TRANSITION
3V
1.5V
0V
t
PLH
t
PHL
t
PHL
V
OL
CONTROL
INPUT
3V
1.5V
0V
3.5V
0V
OUTPUT
NORMALLY
LOW
OUTPUT
NORMALLY
HIGH
SWITCH
CLOSED
SWITCH
OPEN
V
OL
0.3V
0.3V
t
PLZ
t
PZL
t
PZH
t
PHZ
3.5V
0V
1.5V
1.5V
ENABLE
DISABLE
V
OH
PRESET
CLEAR
CLOCK ENABLE
ETC.
Octal link
Octal link
Octal link
Octal link
Octal link
TEST CIRCUITS AND WAVEFORMS
Propagation Delay
Test Circuits for All Outputs
Enable and Disable Times
Set-Up, Hold, and Release Times
Pulse Width
NOTES:
1. Diagram shown for input Control Enable-LOW and input Control Disable-HIGH.
2. Pulse Generator for All Pulses: Rate
1.0MHz; t
F
2.5ns; t
R
2.5ns.
Test
Switch
Open Drain
Disable Low
Closed
Enable Low
All Other Tests
Open
SWITCH POSITION
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse Generator.
INDUSTRIAL TEMPERATURE RANGE
IDT74FCT2245AT/CT
FAST CMOS OCTAL BIDIRECTIONAL TRANSCEIVER
7
ORDERING INFORMATION
IDT XX
Temp. Range
FCT
XXXX
Device Type
XX
Package
Octal Bidirectional Transceiver
2245AT
2245CT
SO
Q
PG
Small Outline IC
Quarter-size Small Outline Package
Thin Shrink Small Outline Package
74
40C to +85C
CORPORATE HEADQUARTERS
for SALES:
for Tech Support:
2975 Stender Way
800-345-7015 or 408-727-6116
logichelp@idt.com
Santa Clara, CA 95054
fax: 408-492-8674
(408) 654-6459
www.idt.com
6/24/2002 Updated as per PDNs Logic-00-07 and Logic-01-04
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