1
IDT74CBTLV3245
LOW-VOLTAGE OCTAL BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
JANUARY 2001
2001 Integrated Device Technology, Inc.
DSC-5170/-
c
IDT74CBTLV3245
INDUSTRIAL TEMPERATURE RANGE
FUNCTIONAL BLOCK DIAGRAM
LOW-VOLTAGE OCTAL
BUS SWITCH
FEATURES:
Pin-out compatible with standard '245 logic
5
A/B bidirectional switch
Isolation Under Power-Off Conditions
Over-voltage tolerant
Latch-up performance exceeds 100mA
V
CC
= 2.3V - 3.6V, Normal Range
ESD > 2000V per MIL-STD-883, Method 3015;
> 200V using machine model (C = 200pF, R = 0)
Available in SSOP, QSOP, and TSSOP packages
DESCRIPTION:
The octal bus switch has standard 245 pinouts. The CBTLV3245 is
designed for asynchronous communication between data buses. When
Output Enable (
OE) is low, the 8-bit bus switch is on and port A is connected
to Port B. When
OE is high, the switch is off and a high impedance exists
between Port A and Port B.
To ensure the high-impedance state during power up or power down,
OE should be tied to V
CC
through a pullup resistor.
APPLICATIONS:
3.3V High Speed Bus Switching and Bus Isolation
OE
A
B
2
9
19
A1
A8
OE
SW
SW
B8
B1
18
11
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
2
INDUSTRIAL TEMPERATURE RANGE
IDT74CBTLV3245
LOW-VOLTAGE OCTAL BUS SWITCH
PIN CONFIGURATION
SSOP/ TSSOP/ QSOP
TOP VIEW
V
CC
OE
B
1
B
2
B
3
B
4
B
5
B
6
B
7
B
8
A
1
A
2
A
3
A
4
A
6
A
7
A
8
GND
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
1
SO20-7
SO20-8
SO20-9
NC
A
5
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Description
Max.
Unit
V
CC
Supply Voltage Range
0.5 to 4.6
V
V
I
Input Voltage Range
0.5 to 4.6
V
Continuous Channel Current
128
mA
I
IK
Input Clamp Current, , V
I/O
< 0
50
mA
T
STG
Storage Temperature
65 to +150
C
NOTE:
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.
PIN DESCRIPTION
Pin Names
Description
OE
Output Enable (Active LOW)
Ax
Port A Inputs or Outputs
Bx
Port B Inputs or Outputs
FUNCTION TABLE
(1)
Input
Operation
OE
L
A Port = B Port
H
Isolation
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
OPERATING CHARACTERISTICS, T
A
= 25C
Symbol
Parameter
Test Conditions
Min.
Max.
Unit
V
CC
Supply Voltage
2.3
3.6
V
V
IH
High-Level Control Input Voltage
V
CC
= 2.3V to 2.7V
1.7
--
V
V
CC
= 2.7V to 3.6V
2
--
V
IL
Low-Level Control Input Voltage
V
CC
= 2.3V to 2.7V
--
0.7
V
V
CC
= 2.7V to 3.6V
--
0.8
T
A
Operating Free-Air Temperature
-
40
+85
C
NOTE:
1. All unused control inputs must be held at V
CC
or GND to ensure proper device operation.
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IDT74CBTLV3245
LOW-VOLTAGE OCTAL BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Operating Condition: T
A
= 40C to +85C
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Unit
V
IK
Control Inputs, Data Inputs
V
CC
= 3V, I
I
=
-
18mA
--
--
1.2
V
I
I
Control Inputs, Data I/O
V
CC
= 3.6V, V
I
= V
CC
or GND
--
--
1
A
I
OZ
Data I/O
V
CC
= 3.6V, V
O
= 0 or 3.6V, switch disabled
--
--
5
A
I
OFF
V
CC
= 0, V
I
or V
O
= 0 to 3.6V
--
--
50
A
I
CC
V
CC
= 3.6V, I
O
= 0, V
I
= V
CC
or GND
--
--
10
A
I
CC (2)
Control Inputs
V
CC
= 3.6V, One input at 3V
,
Other inputs at V
CC
or GND
--
--
300
A
C
I
Control Inputs
V
I
= 3V or 0
--
4
--
pF
C
IO(OFF)
V
O
= 3V or 0,
OE = V
CC
--
6
--
pF
Max at V
CC
= 2.3V
V
I
= 0
I
O
= 64mA
--
5
8
Typ at V
CC
= 2.5V
I
O
= 24mA
--
5
8
R
ON
(3)
V
I
= 1.7V
I
O
= 15mA
--
27
40
V
I
= 0
I
O
= 64mA
--
5
7
V
CC
= 3V
I
O
= 24mA
--
5
7
V
I
= 2.4V
I
O
= 15mA
--
10
15
NOTES:
1. Typical values are at 3.3V, +25
C ambient.
2. The increase in supply current is attributable to each input that is at the specified voltage level rather than V
CC
or GND.
3. This is measured by the voltage drop between the A and B terminals at the indicated current through the switch.
SWITCHING CHARACTERISTICS
V
CC
= 2.5V 0.2V
V
CC
= 3.3V 0.3V
Symbol
Parameter
Min.
Max.
Min.
Max.
Unit
t
PD
(1)
Propagation Delay
A to B or B to A
0.15
0.25
ns
t
EN
Output Enable Time
OE to A or B
1
4.5
1
4.2
ns
t
DIS
Output Disable Time
OE to A or B
1
5
1
5
ns
NOTE:
1. The propagation delay is the calculated RC time constant of the typical on-state resistance of the switch and the specified load capacitance when
driven by an ideal voltage source (zero output impedance).
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INDUSTRIAL TEMPERATURE RANGE
IDT74CBTLV3245
LOW-VOLTAGE OCTAL BUS SWITCH
Open
V
LO AD
GND
V
CC
Pulse
Generator
D.U.T.
500
500
C
L
R
T
V
IN
V
OU T
(1, 2)
SAME PHASE
IN PU T TRANSITION
OPPOSITE PHASE
IN PU T TRANSITION
0V
0V
V
O H
V
O L
t
PLH
t
PH L
t
PH L
t
PLH
OUTPUT
V
IH
V
T
V
T
V
IH
V
T
CONTROL
IN PU T
t
PLZ
0V
OUTPUT
NORMALLY
LOW
t
PZ H
0V
SW ITCH
CL O SE D
OUTPUT
NORMALLY
HIGH
ENABLE
DISABLE
SW ITCH
O P E N
t
PH Z
0V
V
OL +
V
LZ
V
OH
V
T
V
T
t
PZL
V
LO AD/2
V
LO AD/2
V
IH
V
T
V
OL
V
OH -
V
HZ
PROPAGATION DELAY
TEST CIRCUITS FOR ALL OUTPUTS
ENABLE AND DISABLE TIMES
TEST CONDITIONS
Symbol
V
CC
(1)
= 3.3V 0.3V
V
CC
(2)
= 2.5V 0.2V
Unit
V
LOAD
6
2 x Vcc
V
V
IH
3
Vcc
V
V
T
1.5
V
CC
/2
V
V
LZ
300
150
mV
V
HZ
300
150
mV
C
L
50
30
pF
TEST CIRCUITS AND WAVEFORMS
DEFINITIONS:
1. C
L
= Load capacitance: includes jig and probe capacitance.
2. R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse
Generator.
NOTES:
1. Pulse Generator for all pulses: Rate
10MHz; t
F
2.5ns; t
R
2.5ns.
2. Pulse Generator for all pulses: Rate
10MHz; t
F
2ns; t
R
2ns.
SWITCH POSITION
Test
Switch
t
PLZ
/
t
PZL
V
LOAD
t
PHZ/
t
PZH
GND
t
PD
Open
NOTE:
1. Diagram shown for input control Enable-LOW and input Control
Disable-HIGH.
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IDT74CBTLV3245
LOW-VOLTAGE OCTAL BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
ORDERING INFORMATION
IDT
XX
C BTLV
XXX
XX
Package
D evice Type
Temp. Range
PY
Q
PG
74
Shrink S m all Outline Package (SO20-7)
Quarter-size Small Outline Package (SO20-8)
Thin Shrink Small Outline Package (SO20-9)
Low-Voltage Octal B us Sw itch
40C to +85C
3245
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
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