1
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
NOVEMBER 2001
2001 Integrated Device Technology, Inc.
DSC-5875/1
c
IDTQS3VH16861
PRELIMINARY
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH
PRODUCTS 2.5V/
3.3V 20-BIT FLOW-THROUGH PIN OUT,
HIGH BANDWIDTH BUS SWITCH
FUNCTIONAL BLOCK DIAGRAM
DESCRIPTION:
The QS3VH16861 HotSwitch with 20-bit flow-though pin out is a high
bandwidth bus switch. The QS3VH16861 has very low ON resistance,
resulting in under 250ps propagation delay through the switch. The switches
are controlled by active low enable (BEx) controls. 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 QS3VH16861 ideal for high perfor-
mance communications applications.
The QS3VH16861 is characterized for operation from -40C to +85C.
A
0
A
9
B
0
B
9
BE 1
A
10
A
19
B
10
B
19
BE2
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
FEATURES:
N channel FET switches with no parasitic diode to Vcc
--
--
- Isolation under power-off conditions
--
--
- No DC path to Vcc 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
Vcc operation: 2.3V to 3.6V
High bandwidth - up to 500 MHz
LVTTL-compatible control Inputs
Undershoot Clamp Diodes on all switch and control Inputs
Low I/O capacitance, 4pF typical
Available in SSOP and TSSOP packages
APPLICATIONS:
Hot-swapping
10/100 Base-T, Ethernet LAN switch
Low distortion analog switch
Replaces mechanical relay
ATM 25/155 switching
2
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Description
Max.
Unit
V
TERM(2)
Supply Voltage 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. current/pin)
120
mA
T
STG
Storage Temperature
-65 to +150
C
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
.
PIN CONFIGURATION
SSOP/ TSSOP
TOP VIEW
48
NC
V
CC
1
47
BE1
2
A
0
46
3
A
1
B
0
45
4
A
2
B
1
44
5
A
3
B
2
43
6
A
4
B
3
41
8
A
6
B
5
40
9
A
7
B
6
39
10
A
8
B
7
42
7
A
5
B
4
38
11
A
9
B
8
37
GND
12
B
9
36
NC
V
CC
13
35
BE2
14
A
10
34
15
A
11
B
10
33
16
A
12
B
11
32
17
A
13
B
12
31
18
A
14
B
13
29
20
A
16
B
15
28
21
A
17
B
16
27
22
A
18
B
17
30
19
A
15
B
14
26
23
A
19
B
18
25
GND
24
B
19
CAPACITANCE
(T
A
= +25
o
C, f = 1MHz, V
IN
= 0V, V
OUT
= 0V)
Symbol
Parameter
(1)
Typ.
Max.
Unit
C
IN
Control Inputs
3
5
pF
C
I/O
Quickswitch Channels (Switch OFF)
4
6
pF
C
I/O
Quickswitch Channels (Switch ON)
8
12
pF
NOTE:
1. This parameter is guaranteed but not production tested.
PIN DESCRIPTION
Pin Names
Description
BEx
Active LOW Bus Enable
A
0
- A
19
Bus A
B
0
- B
19
Bus B
FUNCTION TABLE
(1)
BE
1
BE
2
A
0
- A
9
A
10
- A
19
Function
L
L
B
0
- B
9
B
10
- B
19
Connect
L
H
B
0
- B
9
Z
Connect B
0
- B
9,
Disconnect B
10
- B
19
H
L
Z
B
10
- B
19
Disconnect B
0
- B
9,
Connect B
10
- B
19
H
H
Z
Z
Disconnect
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
Z = High-Impedence
3
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
(1)
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= 40C to +85C, V
CC
= 3.3V 0.3V
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 HIGH
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
(Typ. 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
NOTE:
1. Typical values are at V
CC
= 3.3V and T
A
= 25C, unless otherwise noted.
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 3.3V
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
R
ON
(ohms)
V
IN
(Volts)
4
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
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
--
1.5
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
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. A and B 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 A and B inputs do not contribute to the Dynamic Power Supply
Current. This parameter is guaranteed but not production tested.
0
2
4
6
8
10
12
14
0
2
4
6
8
10
12
14
16
18
20
TYPICAL I
CCD
vs ENABLE FREQUENCY CURVE AT V
CC
= 3.3V
I
CCD
(mA)
ENABLE FREQUENCY (MHz)
5
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, 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
A to B or B to A
t
PZH
Switch Turn-On Delay
1.5
8.5
1.5
8
ns
t
PZL
BEx to xA or xB
t
PHZ
Switch Turn-Off Delay
1.5
7.5
1.5
7.5
ns
t
PLZ
BEx to xA or xB
f
BEx
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 BEx control input (pass voltage > V
CC
, V
IN
= 5V, R
LOAD
> 1M
, no C
LOAD
).
6
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
PHY
3VH
SW ITCH
4.5V
P P
LOGIC
SIDE
Z = 100
10M bps to 100Mbps
2V
PP
4.5V
P P
LOGIC
SID E
Z = 100
TW ISTED PAIR
>100m
CHARGE PUMP
OE
Vcc = 3.3V
0 to +5V
NFET
+6.5V
DRIVER
0 to +5V
SINGLE HOT
SW ITCH
CARD I/O
ON CARD
LOGIC
CO
NN
E
C
T
O
R
QS
3
V
H
X
X
X
CPU
RAM
BUS
CARD I/O
ON CARD
LOGIC
CO
NN
E
C
T
O
R
QS
3
V
H
X
X
X
PLUGGABLE CARD/ LIVE SYSTEM
ZERO DOW N TIME SYSTEM
Rail-to-Rail Switching
SOME APPLICATIONS FOR HOTSWITCH PRODUCTS
Fast Ethernet Data Switching (LAN Switch)
Hot Swapping
7
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
Open
V
LOAD
GN D
V
CC
Pulse
G enerator
D .U .T.
500
500
C
L
R
T
V
IN
V
OUT
(1, 2)
SAM E PH AS E
IN PUT TR AN SITION
OPPOSITE PHASE
IN PU T TRAN SITIO N
0V
0V
V
OH
V
O L
t
PLH
t
PH L
t
PHL
t
PLH
OU TPUT
V
IH
V
T
V
T
V
IH
V
T
CON TR OL
INPU T
t
PLZ
0V
OU TPU T
N OR M ALLY
LOW
t
PZ H
0V
S W ITCH
CLO SE D
OU TPU T
NO RM ALLY
HIGH
EN ABLE
D ISABLE
SW ITCH
O P E N
t
PH Z
0V
V
O L +
V
LZ
V
O H
V
T
V
T
t
PZL
V
LO AD/2
V
L O A D /2
V
IH
V
T
V
O L
V
O H -
V
H Z
TEST CIRCUITS AND WAVEFORMS
Enable and Disable Times
NOTE:
1. Diagram shown for input Control Enable-LOW and input Control Disable-HIGH.
Propagation Delay
Test Circuits for All Outputs
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse Generator.
NOTES:
1. Pulse Generator for All Pulses: Rate
1.0MHz; t
F
2.5ns; t
R
2.5ns.
2. Pulse Generator for All Pulses: Rate
1.0MHz; t
F
2ns; t
R
2ns.
SWITCH POSITION
Test
Switch
t
PLZ
/
t
PZL
V
LOAD
t
PHZ/
t
PZH
GND
t
PD
Open
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
8
INDUSTRIAL TEMPERATURE RANGE
IDTQS3VH16861
2.5V / 3.3V 20-BIT FLOW-THROUGH PIN OUT, HIGH BANDWIDTH BUS SWITCH
IDTQS
XXXXX
XX
Package
Device Type
3VH16861
2.5V / 3.3V 20-Bit Flow Though Pin Out, High
Bandwidth Bus Switch
PV
PA
Shrink Small Outline Package
Thin Shrink Small Outline Package
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
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