1
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
MAY 2002
INDUSTRIAL TEMPERATURE RANGE
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
2002 Integrated Device Technology, Inc.
DSC-5515/1
FEATURES:
Bus switches provide zero delay paths
Low switch on-resistance: 5
TTL-compatible input and output levels
ESD > 2000V per MIL-STD-883, Method 3015; > 200V using
machine model (C = 200pF, R = 0)
Available in SSOP and TSSOP packages
FUNCTIONAL BLOCK DIAGRAM
IDT74FST163383
20-BIT BUS EXCHANGE
SWITCH
DESCRIPTION:
The FST163383 belongs to IDT's family of Bus switches. Bus switch
devices perform the function of connecting or isolating two ports without
providing any inherent current sink or source capability. Thus they
generate little or no noise of their own while providing a low resistance path
for an external driver. These devices connect input and output ports through
an n-channel FET. When the gate-to-source junction of this FET is
adequately forward-biased the device conducts and the resistance be-
tween input and output ports is small. Without adequate bias on the gate-
to-source junction of the FET, the FET is turned off, therefore with no V
CC
applied, the device has hot insertion capability.
The low on-resistance and simplicity of the connection between input and
output ports reduces the delay in this path to close to zero.
The FST163383 provides four 4-bit TTL- compatible ports that supports
2 way bus exchange. The BX pin controls the bus exchange and the BE
pin serves as the enable pin.
A
0
B
0
A
4
B
4
B
X 1
BE
1
C
0
D
0
C
4
D
4
A
5
B
5
A
9
B
9
B
X 2
BE
2
C
5
D
5
C
9
D
9
2
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
SSOP/ TSSOP
TOP VIEW
PIN CONFIGURATION
Symbol
Description
Max
Unit
V
TERM
(2)
Terminal Voltage with Respect to GND
0.5 to +7
V
T
STG
Storage Temperature
65 to +150
C
I
OUT
Maximum Continuous Channel Current
128
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.
2. Vcc, Control, and Switch terminals.
Pin Names
I/O
Description
A
0-9
, B
0-9
I/O
Buses A, B
C
0-9
, D
0-9
I/O
Buses C, D
BE
1,2
I
Bus Switch Enable (Active LOW)
BE
1,2
I
Bus Exchange
PIN DESCRIPTION
Symbol
Parameter
Conditions
(2)
Typ. Unit
C
IN
Control Input Capacitance
4
pF
C
I/O
Switch Input/Output Capacitance
Switch Off
pF
CAPACITANCE
(1)
NOTES:
1. Capacitance is characterized but not tested.
2. T
A
= 25C, f = 1MHz, V
IN
= 0V, V
OUT
= 0V.
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
Z = High-Impedance
FUNCTION TABLE
(1)
BE
2
BX
2
A
5-9
B
5-9
Description
H
X
Z
Z
Disconnect
L
L
C
5-9
D
5-9
Connect
L
H
D
5-9
C
5-9
Exchange
BE
1
BX
1
A
0-4
B
0-4
Description
H
X
Z
Z
Disconnect
L
L
C
0-4
D
0-4
Connect
L
H
D
0-4
C
0-4
Exchange
5
6
7
8
9
10
1
2
3
4
46
45
44
43
42
41
40
39
38
37
C
2
C
0
A
0
B
0
BE1
D
0
C
1
A
1
B
1
D
1
B
4
A
4
C
4
D
3
B
3
A
3
C
3
D
2
Vcc
D
4
A
2
11
12
47
48
GND
B
2
BX1
17
18
19
20
21
22
13
14
15
16
34
33
32
31
30
29
28
27
26
25
C
7
C
5
A
5
B
5
BE2
D
5
C
6
A
6
B
6
D
6
B
9
A
9
C
9
D
8
B
8
A
8
C
8
D
7
Vcc
D
9
A
7
23
24
35
36
GND
B
7
BX2
3
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
V
IH
Input HIGH Voltage
Guaranteed Logic HIGH for Control Inputs
2
--
--
V
V
IL
Input LOW Voltage
Guaranteed Logic LOW for Control Inputs
--
--
0.8
V
I
IH
Input HIGH Current
V
CC
= Max.
V
I
= V
CC
--
--
1
A
I
IL
Input LOW Current
V
I
= GND
--
--
1
I
OZH
High Impedance Output Current
V
CC
= Max.
V
O
= V
CC
--
--
1
A
I
OZL
(3-State Output Pins)
V
O
= GND
--
--
1
I
OS
Short Circuit Current
Vcc = Max., V
O
= GND
(3)
--
300
--
mA
V
IK
Clamp Diode Voltage
V
CC
= Min., I
IN
= 18mA
--
0.7
1.2
V
R
ON
Switch On Resistance
(4)
Vcc = Min., V
IN
= 0V, I
ON
= 30mA
--
5
7
Vcc = Min., V
IN
= 2.4V, I
ON
= 15mA
--
10
15
I
OFF
Input/Output Power Off Leakage
V
CC
= 0V, V
IN
or V
O
4.5V
--
--
1
A
I
CC
Quiescent Power Supply Current
V
CC
= Max., V
I
= GND or V
CC
--
0.1
3
A
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= 40C to +85C, V
CC
= 5.0V 10%
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
CC
Quiescent Power Supply Current
V
CC
= Max.
--
0.5
1.5
mA
TTL Inputs HIGH
V
IN
= 3.4V
(3)
I
CCD
Dynamic Power Supply
V
CC
= Max.
V
IN
= V
CC
--
30
40
A/
Current
(4)
Outputs Open
V
IN
= GND
MHz/
Enable Pin Toggling
Switch
50% Duty Cycle
I
C
Total Power Supply Current
(5)
V
CC
= Max.
V
IN
= V
CC
--
6
8
mA
Outputs Open
V
IN
= GND
Enable Pins Toggling
(20 Switches Toggling)
V
IN
= V
CC
--
6.5
9.5
f
i
= 10MHz
V
IN
= 3.4V
50% Duty Cycle
POWER SUPPLY CHARACTERISTICS
NOTES:
1. For conditions shown as Max. or Min., 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. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
I
CC
D
H
N
T
+ I
CCD
(f
i
N)
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
i
= Control Input Frequency
N = Number of Control Inputs Toggling at f
i
All currents are in milliamps and all frequencies are in megahertz.
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at Vcc = 5.0V, +25C ambient.
3. Not more than one output should be shorted at one time. Duration of the test should not exceed one second.
4. Measured by voltage drop between ports at indicated current through the switch.
4
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= -40C to +85C, V
CC
= 5.0V 10%
Symbol
Description
(1)
Condition
Min.
Typ.
Max.
Unit
t
PLH
Data Propagation Delay
C
L
= 50pF
--
--
0.25
ns
t
PHL
Ax to Cx, Dx and/or Bx to Cx and/or Dx
(3,4)
R
L
= 500
t
BX
Switch Multiplex Delay
1.5
--
6.5
ns
BX to Ax, Bx, Cx, Dx
t
PZH
Switch Turn On Delay
1.5
--
6.5
ns
t
PZL
BE to Ax, Bx, Cx, Dx
t
PHZ
Switch Turn Off Delay
1.5
--
5.5
ns
t
PLZ
BE to Ax, Bx
(3)
|Q
CI
|
Charge Injection, Typical
(5,6)
--
1.5
--
pC
|Q
DCI
|
Charge Injection, Typical
(6,7)
--
0.5
--
NOTES:
1. See test circuit and waveforms.
2. Minimum limits guaranteed but not tested.
3. This parameter is guaranteed by design but not tested.
4. The bus switch contributes no propagation delay other than the RC delay of the on resistance of the switch and the load capacitance. The time constant for the switch alone is
of the order of 2.5ns for 50pF load. Since this time is constant and much smaller than the rise/fall times of typical driving signals, it adds very little propagation delay to the system.
Propagation delay on the bus switch when used in a system is determined by the driving circuit on the driving side of the switch and its interaction with the load on the driven
side.
5. Measured at switch turn off, load = 50 pF in parallel with 10 M
scope probe, V
IN
= 0.0 volts.
6. Characterized parameter. Not 100% tested.
7. Measured at switch turn off through bus multiplexer, (e.g.- A to C = >A to D), load = 50 pF in parallel with 10 M
scope probe, V
IN
at A = 0.0 volts. Charge injection is reduced
because the injection from the turn off of the A to C switch is compensated by the turn on of the B to C switch.
5
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
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
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.
Propagation Delay
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.
6
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163383
20-BIT BUS EXCHANGE SWITCH
ORDERING INFORMATION
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
5/28/2002 Removed TVSOP package
DATA SHEET DOCUMENT HISTORY
IDT XX
Temp. Range
XXX
Device Type
X
Package
74
40C to +85C
PV
PA
383
Shrink Small Outline Package
Thin Shrink Small Outline Package
20-Bit Bus Exchange Switch
FST
Family
XXX
163
Double-Density Bus Switch
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