1
PS2012B 09/22/99
Product Pin Configuration
Inputs
OE
T/R
Outputs
L
L
Bus B Data to Bus A
(2)
L
H
Bus A Data to Bus B
(2)
H
X
High Z State
1. H = High Voltage Level, X = Don't Care, L = Low
Voltage Level, Z = High Impedance
2. 640 is inverting from input to output.
Truth Table
(1)
Pin Name
Description
OE
3-State Output Enable Inputs (Active LOW)
T/R
Transmit/Receive Input
A
0
-A
7
Side A Inputs or 3-State Outputs
B
0
-B
7
Side B Inputs or 3-State Outputs
GND
Ground
V
CC
Power
Product Pin Description
Fast CMOS Octal
Bidirectional Transceivers
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PI74FCT245T/640T/645T
PI74FCT2245T/2640T/2645T
(25
Series)
FCT245, 2245, 645, 2645 are non-inverting options.
FCT640 & FCT2640 are inverting options.
Logic Block Diagram
Product Description
Pericom Semiconductors PI74FCT series of logic circuits are
produced using the Companys advanced 0.6/0.8 micron CMOS
technology, achieving industry leading speed grades. All
PI74FCT2XXX devices have a built-in 25 Ohm series resistor on all
outputs to reduce noise because of reflections, thus eliminating the
need for an external terminating resistor.
The PI74FCT245T/640T/645T and PI74FCT2245T/2640T/2645T are
8-bit wide octal buffer bidirectional transceivers 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.
Product Features
PI74FCT245/640/645T and PI74FCT2245/2640T/2645T are pin
compatible with bipolar FAST Series at a higher speed and
lower power consumption
25 Ohm series resistor on all outputs (FCT2XXX only)
TTL input and output levels
Low ground bounce outputs
Extremely low static power
Hysteresis on all inputs
Industrial operating temperature range: 40C to +85C
Packages available:
20-pin 173 mil wide plastic TSSOP (L)
20-pin 300 mil wide plastic DIP (P)
20-pin 150 mil wide plastic QSOP (Q)
20-pin 150 mil wide plastic TQSOP (R)
20-pin 300 mil wide plastic SOIC (S)
20-pin 209 mil wide plastic SSOP (H)
Device models available on request
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
T/R
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
GND
Vcc
OE
B
0
B
1
B
2
B
3
B
4
B
5
B
6
B
7
20-Pin
L,P,Q
R,S,H
A0
B0
OE
A1
B1
A2
B2
A3
B3
A4
B4
A5
B5
A6
B6
A7
B7
T/R
2
PS2012B 09/22/99
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PI74FCT245T/640T/645T
25 Ohm Series PI74FCT2245T/2640T/2645T
Octal BidirectionalTransceivers
Storage Temperature .................................................................... 65C to +150C
Ambient Temperature with Power Applied ....................................40C to +85C
Supply Voltage to Ground Potential (Inputs & V
CC
Only) ............. 0.5V to +7.0V
Supply Voltage to Ground Potential (Outputs & D/O Only) ........... 0.5V to +7.0V
DC Input Voltage ............................................................................ 0.5V to +7.0V
DC Output Current ...................................................................................... 120mA
Power Dissipation ..........................................................................................0.5W
Note:
Stresses greater than those listed under 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.
DC Electrical Characteristics
(Over the Operating Range, T
A
= 40C to +85C, V
CC
= 5.0V 5%)
Parameters Description
Test Conditions
(1)
Min. Typ
(2)
Max. Units
V
OH
Output HIGH Voltage
V
CC
= Min., V
IN
= V
IH
or V
IL
I
OH
= 15.0mA
2.4
3.0
V
V
OL
Output LOW Current
V
CC
= Min., V
IN
= V
IH
or V
IL
I
OL
= 64mA
0.3
0.55
V
V
OL
Output LOW Current
V
CC
= Min., V
IN
= V
IH
or V
IL
I
OL
= 12mA (25
Series)
0.3
0.50
V
V
IH
Input HIGH Voltage
Guaranteed Logic HIGH Level
2.0
V
V
IL
Input LOW Voltage
Guaranteed Logic LOW Level
0.8
V
I
IH
Input HIGH Current
(Except I/O pins) V
CC
= Max.
V
IN
= V
CC
1
A
I
IL
Input LOW Current
(Except I/O pins) V
CC
= Max.
V
IN
= GND
1
A
I
IH
Input HIGH Current
(I/O pins Only) V
CC
= Max.
V
IN
= V
CC
1
A
I
IL
Input LOW Current
(I/O pins Only) V
CC
= Max.
V
IN
= GND
1
A
I
OZH
High Impedance
V
CC
= M
AX
.
V
OUT
= 2.7V
1
A
I
OZL
Output Current
V
OUT
= 0.5V
1
A
V
IK
Clamp Diode Voltage
V
CC
= Min., I
IN
= 18 mA
0.7
1.2
V
I
OFF
Power Down Disable
V
CC
= GND, V
OUT
= 4.5V
--
--
100
A
I
OS
Short Circuit Current
V
CC
= Max.
(3)
, V
OUT
= GND
60
120
mA
V
H
Input Hysteresis
200
mV
Capacitance
(T
A
= 25C, f = 1 MHz)
Parameters
(4)
Description
Test Conditions
Typ.
Max.
Units
C
IN
Input Capacitance
V
IN
= 0V
6
10
pF
C
OUT
Output Capacitance
V
OUT
= 0V
8
12
pF
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 5.0V, +25C ambient and maximum loading.
3. Not more than one output should be shorted at one time. Duration of the test should not exceed one second.
4. This parameter is determined by device characterization but is not production tested.
Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
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PS2012B 09/22/99
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PI74FCT245T/640T/645T
25 Ohm Series PI74FCT2245T/2640T/2645T
Octal BidirectionalTransceivers
Power Supply Characteristics
Parameters Description
Test Conditions
(1)
Min.
Typ
(2)
Max.
Units
I
CC
Quiescent Power
V
CC
= Max.
V
IN
= GND or V
CC
0.1
500
A
Supply Current
I
CC
Supply Current per
V
CC
= Max.,
V
IN
= 3.4V
(3)
0.5
2.0
mA
Input @ TTL HIGH
I
CCD
Supply Current per
V
CC
= Max.,
V
IN
= V
CC
0.15
0.25
mA/
Input per MHz
(4)
Outputs Open
V
IN
= GND
MHz
OE = GND
T/R = GND or V
CC
One Input Toggling
50% Duty Cycle
I
C
Total Power Supply
V
CC
= Max.,
V
IN
= V
CC
1.5
3.5
(5)
mA
Current
(6)
Outputs Open
V
IN
= GND
f
I
= 10 MH
Z
50% Duty Cycle
V
IN
= 3.4V
1.8
4.5
(5)
T/R = OE = GND
V
IN
= GND
One Bit Toggling
V
CC
= Max.,
V
IN
= V
CC
3.0
6.0
(5)
Outputs Open
V
IN
= GND
f
I
= 2.5 MH
Z
50% Duty Cycle
V
IN
= 3.4V
5.0
14.0
(5)
T/R = OE = GND
V
IN
= GND
Eight Bits Toggling
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device.
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 the Icc formula. These limits are guaranteed but not tested.
6. I
C
=I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+ DI
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
= Input Frequency
N
I
= Number of Inputs at f
I
All currents are in milliamps and all frequencies are in megahertz.
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PS2012B 09/22/99
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PI74FCT245T/640T/645T
25 Ohm Series PI74FCT2245T/2640T/2645T
Octal BidirectionalTransceivers
PI74FCT245T/2245T Switching Characteristics over Operating Range
245T/2245T
245AT/2245AT 245CT/2245CT
245DT
Com.
Com.
Com.
Com.
Parameters Description
Conditions
(1)
Min.
Max.
Min.
Max.
Min.
Max.
Min
Max. Unit
t
PLH
Propagation Delay
C
L
= 50 pF
1.5
7.0
1.5
4.6
1.5
4.1
1.5
3.8
ns
t
PHL
A to B, B to A
R
L
= 500 Ohm
t
PZH
Output Enable Time
1.5
9.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
OE to A or B
t
PHZ
Output Disable Time
1.5
7.5
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
OE to A or B
(3)
t
PZH
Output Enable Time
1.5
9.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
T/R to A or B
t
PHZ
Output Disable Time
(3)
1.5
7.5
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
T/R to A or B
(3)
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 production tested.
PI74FCT640T/2640T Switching Characteristics over Operating Range
640T/2640T
640AT/2640AT 640CT/2640CT
640DT
Com.
Com.
Com.
Com.
Parameters Description
Conditions
(1)
Min.
Max.
Min.
Max.
Min.
Max.
Min.
Max. Unit
t
PLH
Propagation Delay
C
L
= 50 pF
2.0
7.0
1.5
5.0
1.5
4.4
1.5
3.7
ns
t
PHL
A to B, B to A
R
L
= 500 Ohm
t
PZH
Output Enable Time
2.0
13.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
OE to A or B
t
PHZ
Output Disable Time
2.0
10.0
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
OE to A or B
(3)
t
PZH
Output Enable Time
2.0
13.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
T/R to A or B
t
PHZ
Output Disable Time
(3)
2.0
10.0
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
T/R to A or B
(3)
PI74FCT645T/2645T Switching Characteristics over Operating Range
645T/2645T
645AT/2645AT 645CT/2645CT
645DT
Com.
Com.
Com.
Com.
Parameters Description
Conditions
(1)
Min.
Max.
Min.
Max.
Min.
Max.
Min.
Max. Unit
t
PLH
Propagation Delay
C
L
= 50 pF
1.5
9.5
1.5
4.6
1.5
4.1
1.5
3.8
ns
t
PHL
A to B, B to A
R
L
= 500 Ohm
t
PZH
Output Enable Time
1.5
11.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
OE to A or B
t
PHZ
Output Disable Time
1.5
12.0
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
OE to A or B
(3)
t
PZH
Output Enable Time
1.5
11.0
1.5
6.2
1.5
5.8
1.5
5.0
ns
t
PZL
T/R to A or B
t
PHZ
Output Disable Time
(3)
1.5
12.0
1.5
5.0
1.5
4.8
1.5
4.3
ns
t
PLZ
T/R to A or B
(3)
Pericom Semiconductor Corporation
2380 Bering Drive San Jose, CA 95131 1-800-435-2336 Fax (408) 435-1100 http://www.pericom.com
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