1
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
MAY 2002
INDUSTRIAL TEMPERATURE RANGE
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
2002 Integrated Device Technology, Inc.
DSC-5866/1
FEATURES:
Bus switches provide zero delay paths
Low switch on-resistance: 4
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
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH
WITH BUS TERMINATOR
DESCRIPTION:
The FST163292 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. 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 between 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 not 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 FST163292 provides four 12-bit TTL-compatible ports that support
2 way bus exchange. The S
0
pin controls the bus exchange and switch
enable functions.
1
A
1
1
A
2
1
B
1
1
B
2
FLOW CO NTRO L
S
0
1 of 12 Channels
500
2
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
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.
Symbol
Parameter
Conditions
(2)
Typ. Unit
C
IN
Control Input Capacitance
8
pF
C
OFF
Switch Input/Output Capacitance
Switch Off
20
pF
C
ON
A/B Capacitance
Switch On
40
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
FUNCTION TABLE
(1)
S
0
A
1
A
2
Function
L
B
1
B
2
A
1
to B
1
, A
2
to B
2
H
B
2
B
1
A
1
to B
2
, A
2
to B
1
Pin Names
I/O
Description
A
1
, A
2
I/O
Buses A
1
, A
2
, B
1
, B
2
B
1
, B
2
S
0
I
Control Pin for Mux and Switch Enable Functions
PIN DESCRIPTION
S
0
1
A
1
NC
2
A
1
NC
3
A
1
NC
GND
V
CC
7
A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
48
49
50
51
52
53
54
55
56
1
4
A
1
NC
5
A
1
NC
6
A
1
NC
NC
8
A
1
GND
NC
9
A
1
NC
10
A
1
NC
NC
1
B
1
1
B
2
2
B
1
2
B
2
3
B
1
GND
7
B
2
3
B
2
4
B
1
4
B
2
5
B
1
5
B
2
6
B
1
7
B
1
8
B
1
GND
8
B
2
9
B
1
9
B
2
10
B
1
10
B
2
NC
6
B
2
26
27
28
31
30
29
11
A
1
NC
12
A
1
NC
11
B
1
11
B
2
12
B
1
12
B
2
25
32
3
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
V
IH
Control Input HIGH Voltage
Guaranteed Logic HIGH for Control Inputs
2
--
--
V
V
IL
Control Input LOW Voltage
Guaranteed Logic LOW for Control Inputs
--
--
0.8
V
I
IH
Control Input HIGH Current
V
CC
= Max.
V
I
= V
CC
--
--
1
A
I
IL
Control Input LOW Current
V
I
= GND
--
--
1
I
OZH
Current During
V
CC
= Max., V
O
= 0 to 5V
--
--
1
A
I
OZL
Bus Switch Disconnect
--
--
1
V
IK
Clamp Diode Voltage
V
CC
= Min., I
IN
= 18mA
--
0.7
1.2
V
I
OFF
Switch Power Off Leakage
V
CC
= 0V, V
IN
or V
O
5.5V
--
--
1
A
I
CC
Quiescent Power Supply Current
V
CC
= Max., V
IN
= 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%
BUS SWITCH IMPEDANCE OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= -40C to +85C, V
CC
= 5.0V 10%
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Unit
Vcc = Min., V
IN
= 0V, I
ON
= 64mA
--
5
7
R
ON
Switch CONNECT Resistance
(2)
Vcc = Min., V
IN
= 0V, I
ON
= 30mA
--
10
12
Vcc = Min., V
IN
= 2.4V, I
ON
= 15mA
--
12
15
I
OS
Short Circuit Current
(3)
Vcc = Max., V
O
= GND
--
300
--
mA
NOTES:
1. Typical values are at Vcc = 5.0V, +25C ambient.
2. The voltage drop between the indicated ports divided by the current through the switch.
3. Not more than one output should be shorted at one time. Duration of the test should not exceed one second.
4
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
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., Outputs Open
V
IN
= V
CC
--
30
40
A/
Current
(4,5)
Select Pin Toggling
V
IN
= GND
MHz/
50% Duty Cycle
Select
I
C
Total Power Supply Current
(6)
V
CC
= Max., Outputs Open
V
IN
= V
CC
--
7.2
9.6
mA
Select Pin Toggling
V
IN
= GND
(24 Switches Toggling)
f
i
= 10MHz
V
IN
= 3.4V
--
7.7
11.1
50% Duty Cycle
V
IN
= GND
POWER SUPPLY CHARACTERISTICS
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type. T
A
= 40C to +85C
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. Switch inputs do not contribute to
I
CC.
4. This parameter represents the current required to switch the internal capacitance of the control inputs at the specified frequency.
Switch inputs generate no significant power supply currents as they transition. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. C
PD
= I
CCD
/V
CC
C
PD
= Power Dissipation Capacitance
6. 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
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= -40C to +85C, V
CC
= 5.0V 10%
V
CC
= 5V 10%
V
CC
= 4V
Symbol
Description
(1)
Min.
Typ.
Max.
Max.
Unit
t
PLH
Data Propagation Delay
--
--
0.25
0.25
ns
t
PHL
A to B, B to A
(2)
t
BX
Switch Multiplex Delay
1.5
--
6.5
7
ns
S to A, B
t
PZH
Switch Turn On Delay
1.5
--
6.5
7
ns
t
PZL
S to A, B
t
PHZ
Switch Turn Off Delay
1.5
--
7
7
ns
t
PLZ
S to A, B
|Q
DCI
|
Charge Injection During Switch Multiplex,
--
0.5
--
--
pC
Sx to xAx or xBx
(3)
t
M
Make-Before-Break Time
0
--
2
2
ns
NOTES:
1. See test circuits and waveforms.
2. The bus switch contributes no Propagation Delay other than the RC Delay of the load interacting with the RC of the switch.
3. |Q
DCI
| is the charge injection for a multiplexer as the multiplexed port switches from one path to another. Charge injection is reduced because the injection from the DISCONNECT
of the first path is compensated by the CONNECT of the second path.
5
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
D.U.T.
V
CC
1 MHz
Signal
Generator
C
L
=
50pF
V
OUT
Switch
Out
Enable/Select
Switch In
Switch In
(MUX)
(1)
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
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
(2)
(3)
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.
Charge Injection
NOTES:
1. Select is used with multiplexers for measuring IQ
DCI
I during multiplexer select. During
all other tests Enable is used.
2. Used with multiplexers to measure IQ
DCI
I only.
3. Charge Injection =
V
OUT
C
L
, with Enable toggling for IQ
CI
I or Select toggling for IQ
DCI
I.
V
OUT
is the change in V
OUT
and is measured with a 10M
probe.
6
INDUSTRIAL TEMPERATURE RANGE
IDT74FST163292
24-BIT BUS EXCHANGE SWITCH WITH BUS TERMINATOR
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
FST
XXX
XX
Package
Device Type
Temp. Range
PV
PA
292
74
Shrink Small Outline Package
Thin Shrink Small Outline Package
24-Bit Bus Exchange Switch
40C to +85C
163
Double-Density Bus Switch
XXX
Family
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