1
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
MARCH 2003
2003 Integrated Device Technology, Inc.
DSC-5596/9
c
IDTQS3VH257
PRELIMINARY
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH
PRODUCTS 2.5V/3.3V
QUAD 2:1 MUX/DEMUX HIGH BAND-
WIDTH BUS SWITCH
FUNCTIONAL BLOCK DIAGRAM
DESCRIPTION:
The QS3VH257 HotSwitch Quad 2:1 multiplexer/demultiplexer is a high
bandwidth bus switch. The QS3VH257 has very low ON resistance, resulting
in under 250ps propagation delay through the switch. The Select (S) input
controls the data flow. The multiplexers/demultiplexers are enabled when the
Enable (E) input is low. In the ON state, the switches can pass signals up to 5V.
In the OFF state, the switches offer very high impedence at the terminals.
The combination of near-zero propagation delay, high OFF impedance, and
over-voltage tolerance makes the QS3VH257 ideal for high performance
communication applications.
The QS3VH257 is characterized for operation from -40
C to +85C.
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
APPLICATIONS:
Hot-swapping
Multiplexing/demultiplexing
Low distortion analog switch
Replaces mechanical relay
ATM 25/155 switching
FEATURES:
N channel FET switches with no parasitic diode to V
CC
Isolation under power-off conditions
No DC path to V
CC
or GND
5V tolerant in OFF and ON state
5V tolerant I/Os
Low R
ON
- 4
typical
Flat R
ON
characteristics over operating range
Rail-to-rail switching 0 - 5V
Bidirectional dataflow with near-zero delay: no added ground
bounce
Excellent R
ON
matching between channels
V
CC
operation: 2.3V to 3.6V
High bandwidth - up to 500MHz
LVTTL-compatible control Inputs
Undershoot Clamp Diodes on all switch and control Inputs
Low I/O capacitance, 4pF typical
Available in QSOP, SOIC, and TSSOP packages
Y
A
B
C
D
I0
A
A
B
B
C
C
D
D
I1
I0
I1
I0
I1
I0
I1
Y
Y
Y
S
E
2
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
PIN CONFIGURATION
Symbol
Description
Max
Unit
V
TERM
(2)
SupplyVoltage to Ground
0.5 to +4.6
V
V
TERM
(3)
DC Switch Voltage V
S
0.5 to +5.5
V
V
TERM
(3)
DC Input Voltage V
IN
0.5 to +5.5
V
V
AC
AC Input Voltage (pulse width
20ns)
3
V
I
OUT
DC Output Current (max. sink current/pin)
120
mA
T
STG
Storage Temperature
65 to +150
C
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. V
CC
terminals.
3. All terminals except V
CC
.
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
Z = High-Impedence
Inputs
Outputs
E
S
Y
A
Y
B
Y
C
Y
D
Function
H
X
Z
Z
Z
Z
Disable
L
L
I0
A
I0
B
I0
C
I0
D
Select 0
L
H
I1
A
I1
B
I1
C
I1
D
Select 1
FUNCTION TABLE
(1)
QSOP/ SOIC/ TSSOP
TOP VIEW
1
2
3
4
5
6
7
16
15
14
13
12
11
10
I
0A
I
1A
I
0B
I
1B
GND
V
CC
I
0D
I
1D
E
I
0C
I
1C
S
Y
A
Y
D
8
9
Y
B
Y
C
Symbol
Parameter
(1)
Typ.
Max.
Unit
C
IN
Control Inputs
3
5
pF
C
I/O
Quickswitch Channels
Demux
4
6
pF
(Switch OFF)
Mux
7
9
C
I/O
Quickswitch Channels
Demux
10
15
pF
(Switch ON)
Mux
10
15
CAPACITANCE
(T
A
= +25C, F = 1MHz, V
IN
= 0V, V
OUT
= 0V)
NOTE:
1. This parameter is guaranteed but not production tested.
Pin Names
I/O
Description
Ixx
I
Data Inputs
S
I
Select Input
E
I
Enable Input
Y
A
- Y
D
O
Data Outputs
PIN DESCRIPTION
3
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 3.3V
R
ON
(ohms)
V
IN
(Volts)
16
14
12
10
8
6
4
2
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
5.0
4.5
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Unit
V
IH
Input HIGH Voltage
Guaranteed Logic HIGH
V
CC
= 2.3V to 2.7V
1.7
--
--
V
for Control Inputs
V
CC
= 2.7V to 3.6V
2
--
--
V
IL
Input LOW Voltage
Guaranteed Logic LOW
V
CC
= 2.3V to 2.7V
--
--
0.7
V
for Control Inputs
V
CC
= 2.7V to 3.6V
--
--
0.8
I
IN
Input Leakage Current (Control Inputs)
0V
V
IN
V
CC
--
--
1
A
I
OZ
Off-State Current (Hi-Z)
0V
V
OUT
5V, Switches OFF
--
--
1
A
I
OFF
Data Input/Output Power Off Leakage
V
IN
or V
OUT
0V to 5V, V
CC
= 0V
--
--
1
A
V
CC
= 2.3V
V
IN
= 0V
I
ON
= 30mA
--
6
8
R
ON
Switch ON Resistance
Typical at V
CC
= 2.5V
V
IN
= 1.7V
I
ON
= 15mA
--
7
9
V
CC
= 3V
V
IN
= 0V
I
ON
= 30mA
--
4
6
V
IN
= 2.4V
I
ON
= 15mA
--
5
8
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= 40C to +85C, V
CC
= 3.3V 0.3V
NOTE:
1. Typical values are at V
CC
= 3.3V and T
A
= 25C.
4
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
TYPICAL I
CCD
vs ENABLE FREQUENCY CURVE AT V
CC
= 3.3V
I
CCD
(mA)
ENABLE FREQUENCY (MHz)
NOTES:
1. For conditions shown as Min. or Max., use the appropriate values specified under DC Electrical Characteristics.
2. Per input driven at the specified level. Mux/demux pins do not contribute to
Icc.
3. This parameter is guaranteed but not tested.
4. This parameter represents the current required to switch internal capacitance at the specified frequency. The mux/demux inputs do not contribute to the Dynamic Power Supply
Current. This parameter is guaranteed but not production tested.
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
Max.
Unit
I
CCQ
Quiescent Power Supply Current
V
CC
= Max., V
IN
= GND or V
CC
, f = 0
--
1
3
mA
I
CC
Power Supply Current
(2,3)
per Input HIGH
V
CC
= Max., V
IN
= 3V, f = 0 per Control Input
--
--
30
A
I
CCD
Dynamic Power Supply Current
(4)
V
CC
= 3.3V, A and B Pins Open, Control Inputs
See Typical I
CCD
vs Enable Frequency graph below
Toggling @ 50% Duty Cycle
0
2
4
6
8
0
2
4
6
8
10
12
14
16
18
20
5
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
T
A
= -40C to +85C
V
CC
= 2.5 0.2V
(1)
V
CC
= 3.3 0.3V
(1)
Symbol
Parameter
Min
.
(4)
Max.
Min
.
(4)
Max.
Unit
t
PLH
Data Propagation Delay
(2,3)
0.2
0.2
ns
t
PHL
Yx to Ixx or Ixx to Yx
t
SEL
Select Time
1.5
9
1.5
8
ns
S to Yx
t
PZH
Enable Time
1.5
9
1.5
9
ns
t
PZL
S to Ixx
t
PHZ
Disable Time
1.5
8
1.5
8
ns
t
PLZ
S to Ixx
t
PZH
Enable Time
1.5
9
1.5
8
ns
t
PZL
E to Yx or Ixx
t
PHZ
Disable Time
1.5
8
1.5
8
ns
t
PLZ
E to Yx or Ixx
f
EorS
Operating Frequency - Enable
(2,5)
10
20
MHz
NOTES:
1. See Test Conditions under TEST CIRCUITS AND WAVEFORMS.
2. This parameter is guaranteed but not production tested.
3. 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 0.2ns at C
L
= 50pF. Since this time constant is much smaller than the rise and 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.
4. Minimums are guaranteed but not production tested.
5. Maximum toggle frequency for S or E control input (pass voltage > V
CC
, V
IN
= 5V, R
LOAD
1M, no C
LOAD
).
6
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
MEM OR Y
MEM OR Y
CPU
M ULTIPLEXING
C ON TR OL CIR CU ITRY
C HAR G E PU MP
O E
Vcc = 3.3V
0 to +5V
N FET
+6.5V
D RIVER
0 to + 5V
SIN GLE H O T
SW ITC H
C AR D I/O
O N C AR D
LOG IC
CON
N
E
C
T
O
R
QS
3
V
H
X
X
X
CPU
R AM
BUS
C AR D I/O
O N C AR D
LOG IC
CO
NN
E
C
T
O
R
QS
3
V
H
X
X
X
PLUG G ABLE CAR D/ LIVE SYSTEM
ZERO DO W N TIM E SYSTEM
Rail-to-Rail Switching
SOME APPLICATIONS FOR HOTSWITCH PRODUCTS
Multiplexing / Demultiplexing
Hot-Swapping
7
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
TEST CIRCUITS AND WAVEFORMS
Open
V
LOAD
G ND
V
CC
Pulse
Generator
D.U.T.
500
500
C
L
R
T
V
IN
V
OUT
(1, 2)
SAM E PH ASE
IN PU T TRANSITION
O PPOSITE PH ASE
IN PUT TR AN SITION
0V
0V
V
OH
V
OL
t
PLH
t
PHL
t
PHL
t
PLH
OU TPUT
V
IH
V
T
V
T
V
IH
V
T
C ON TRO L
IN PU T
t
PLZ
0V
O UTPU T
N OR M ALLY
LOW
t
PZ H
0V
SW ITCH
CLO SED
OUTPU T
N OR M ALLY
H IGH
EN ABLE
D ISABLE
SW ITCH
O PE N
t
PHZ
0 V
V
O L +
V
LZ
V
O H
V
T
V
T
t
PZL
V
LOAD/2
V
LO A D /2
V
IH
V
T
V
O L
V
O H -
V
H Z
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
NOTE:
1. Diagram shown for input Control Enable-LOW and input Control Disable-HIGH.
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.
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse Generator.
SWITCH POSITION
Test
Switch
t
PLZ
/
t
PZL
V
LOAD
t
PHZ/
t
PZH
GND
t
PD
Open
Propagation Delay
Test Circuits for All Outputs
Enable and Disable Times
8
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH257
2.5V / 3.3V QUAD 2:1 MUX/DEMUX HIGH BANDWIDTH BUS SWITCH
ORDERING INFORMATION
IDTQS
XXXXX
XX
Package
Device Type
3VH257
2.5V / 3.3V Quad 2:1 Mux/Demux High
Bandwidth Bus Switch
S1
Q
PA
Small Outline IC
Quarter Size Outline Package
Thin Shrink Small Outline Package
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
8/6/2002
Updated according to PCN Logic-0206-11
3/3/2003
Changed Icc limits
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