1
IDT74FST3390
OCTAL 2:1 MULTIPLEXER BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
OCTOBER 1999
1999 Integrated Device Technology, Inc.
DSC-5527/-
c
IDT74FST3390
COMMERCIAL TEMPERATURE RANGE
OCTAL 2:1 MULTIPLEXER
BUS SWITCH
DESCRIPTION:
The FST3390 belongs to IDT's family of Bus switches. Bus switch
devices perform the function of connecting or isolating two ports without
A
0
C
0
A
7
C
7
B
0
B
7
AEN
BEN
5
6
7
8
9
10
1
2
3
4
26
25
24
23
22
21
20
19
18
17
A
3
B
0
C
0
A
1
A
0
B
1
C
1
A
2
B
2
C
2
B
7
C
7
A
6
B
6
C
6
A
5
B
5
C
5
Vcc
A
7
SO 28-2
SO 28-8
SO 28-9
B
3
11
12
27
28
C
3
A
4
B
4
16
15
AEN
13
14
G ND
C
4
BEN
SOIC/ QSOP/ TSSOP
TOP VIEW
FUNCTIONAL BLOCK DIAGRAM
PIN CONFIGURATION
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 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 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 FST3390 is an 8-bit TTL-compatible 2:1 bus multiplexer.
AEN =
0 connects port A to port C and
BEN = 0 connects port B to port C. This
device can be used to connect ports A & B to a common bus on port C or
to broadcast data on port C to both ports A and B.
FEATURES:
-
Bus switches provide zero delay paths
-
Extended commercial range of 40C to +85C
-
Low switch on-resistance: FST3xxx 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 SOIC, QSOP, and TSSOP Packages
2
COMMERCIAL TEMPERATURE RANGE
IDT74FST3390
OCTAL 2:1 MULTIPLEXER BUS SWITCH
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Rating
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
FST LINK
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.
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. Not more than one output should be tested 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.
CAPACITANCE
(1)
Symbol
Parameter
Conditions
(2)
Typ.
Unit
C
IN
Control Input Capacitance
4
pF
C
I/O
Switch Input/Output
Capacitance
Switch Off
pF
NOTES:
1. Capacitance is characterized but not tested.
2. T
A
= 25C, f = 1MHz, V
IN
= 0V, V
OUT
= 0V
PIN DESCRIPTION
Pin Names
I/O
Description
A
0-7
I/O
Bus A
B
0-7
I/O
Bus B
C
0-7
I/O
Bus C
AEN, BEN
I
Bus Switch Enable (Active LOW)
FUNCTION TABLE
(1)
AEN
BEN
A
B
Description
H
H
Off
Off
Disconnect
L
H
On
Off
A to C
H
L
Off
On
B to C
L
L
On
On
A, B to C
NOTE:
1. H = HIGH
L = LOW
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Commercial: T
A
= 0C to +70C, V
CC
= 5.0V 5%
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 Voltage
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
V
CC
= 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)
V
CC
= Min. V
IN
= 0.0V
--
5
7
I
ON
= 30mA
V
CC
= Min. V
IN
= 2.4V
--
10
15
I
ON
= 15mA
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
3
IDT74FST3390
OCTAL 2:1 MULTIPLEXER BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
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. Values for these conditions are examples of the 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
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
= Input Frequency
N = Number of Switches Toggling at f
i
All currents are in milliamps and all frequencies are in megahertz.
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 0.25 ns for 50 pF 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 of 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 volts.
6. Characterized parameter. Not 100% tested.
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
CC
Quiescent Power Supply Current
TTL Inputs HIGH
V
CC
= Max.
V
IN
= 3.4V
(3)
--
0.5
1.5
mA
I
CCD
Dynamic Power Supply Current
(4)
V
CC
= Max.
Outputs Open
V
IN
= V
CC
V
IN
= GND
--
30
40
A/
MHz/
Enable Pin Toggling
50% Duty Cycle
Switch
I
C
Total Power Supply Current
(6)
V
CC
= Max.
Outputs Open
Enable Pin Toggling
V
IN
= V
CC
V
IN
= GND
--
2.4
3.2
mA
(8 Switches Toggling)
fi = 10MHz
50% Duty Cycle
V
IN
= 3.4
V
IN
= GND
--
2.7
4
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
Symbol
Description
Condition
(1)
Min.
(2)
Typ.
Max.
Unit
t
PLH
t
PHL
Data Propagation Delay
A, B to/from C
(3,4)
C
L
= 50pF
R
L
= 500
--
--
0.25
ns
t
PZH
t
PZL
Switch Turn on Delay
AEN/BEN to A, B, C
1.5
--
6.5
ns
t
PHZ
t
PLZ
Switch Turn off Delay
AEN, BEN to A, B, C
(3)
1.5
--
5.5
ns
|Q
CI
|
Charge Injection
(5,6)
--
1.5
--
pC
4
COMMERCIAL TEMPERATURE RANGE
IDT74FST3390
OCTAL 2:1 MULTIPLEXER BUS 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
IN PU T
TIM IN G
IN PU T
ASYN CH R ON OUS C ON TROL
PRES ET
CLEAR
ETC.
SYNC HRO N OU S CON TRO L
t
SU
t
H
t
REM
t
SU
t
H
HIGH-LOW -HIGH
PULSE
LO W -H IGH -LOW
PULSE
t
W
1.5V
1.5V
SAM E PHASE
IN PU T TR ANSITION
3V
1.5V
0V
1.5V
V
OH
t
PLH
OU TPUT
OPPOSITE P HASE
IN PU T TR ANSITION
3V
1.5V
0V
t
PLH
t
PH L
t
PH L
V
OL
CO NTR OL
IN PU T
3V
1.5V
0V
3.5V
0V
OU TPUT
NO RM A LLY
LO W
OU TPUT
NO RM A LLY
HIGH
SW ITC H
CLOSE D
SW ITC H
OPEN
V
OL
0.3V
0.3V
t
PLZ
t
PZL
t
PZH
t
PHZ
3.5V
0V
1.5V
1.5V
ENAB LE
DISA BLE
V
OH
PRES ET
CLEAR
CLOC K ENABLE
ETC.
O ctal lin k
O ctal lin k
O ctal lin k
O ctal lin k
O ctal lin k
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
SWITCH POSITION
Test
Switch
Open Drain
Disable Low
Closed
Enable Low
All Other Tests
Open
FCT LINK
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse
Generator.
5
IDT74FST3390
OCTAL 2:1 MULTIPLEXER BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
CORPORATE HEADQUARTERS
for SALES:
2975 Stender Way
800-345-7015 or 408-727-6116
Santa Clara, CA 95054
fax: 408-492-8674
www.idt.com*
*To search for sales office near you, please click the sales button found on our home page or dial the 800# above and press 2.
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
ORDERING INFORMATION
IDT XX
Temp. Range
XXXX
Device Type
X
Package
74
-
40
C to +85
C
SO
Q
PG
3390
Small Outline IC (SO28-2)
Quarter-size Small Outline Package (SO28-8)
Thin Shrink Small Outline Package (SO28-9)
Octal 2:1 Multiplexer Bus Switch
FST
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