2.5V / 3.3V 20-BIT HIGH BANDWIDTH BUS SWITCH WITH PRECHARGED OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH
®
PRODUCTS
2.5V / 3.3V 20-BIT HIGH
BANDWIDTH BUS SWITCH
WITH PRECHARGED OUTPUTS
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
• B port precharged to user-selectable V
BIAS
• Low R
ON
- 4Ω typical
Ω
• 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 TSSOP package
IDTQS3VH16800
DESCRIPTION:
The QS3VH16800 HotSwitch is a 20-bit high bandwidth bus switch. The
QS3VH16800 has very low ON resistance, resulting in under 250ps propa-
gation delay through the switch. The QS3VH16800 precharges the B port to
a user selectable bias voltage (V
BIAS
) to minimize live insertion noise. The
switches can be turned ON under the control of the LVTTL-compatible Output
Enable signal for bidirectional data flow with no added delay or ground bounce.
It can be used as two 10-bit bus switches or one 20-bit bus switch. In the OFF
and ON states, the switches are 5V-tolerant. 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 QS3VH16800 ideal for high performance
communications applications.
The QS3VH16800 is characterized for operation from -40°C to +85°C.
APPLICATIONS:
•
•
•
•
•
Hot-swapping
10/100 Base-T, Ethernet LAN switch
Low distortion analog switch
Replaces mechanical relay
ATM 25/155 switching
FUNCTIONAL BLOCK DIAGRAM
V
BIAS
V
BIAS
A
0
B
0
A
10
B
10
A
9
B
9
A
19
B
19
OE1
OE2
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
INDUSTRIAL TEMPERATURE RANGE
1
c
2006 Integrated Device Technology, Inc.
JUNE 2006
DSC-5961/8
IDTQS3VH16800
2.5V / 3.3V 20-BIT HIGH BANDWIDTH BUS SWITCH WITH PRECHARGED OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
TERM
(2)
V
TERM
(3)
V
TERM
(3)
Description
SupplyVoltage to Ground
DC Switch Voltage V
S
DC Input Voltage V
IN
AC Input Voltage (pulse width
≤20ns)
DC Output Current (max. sink current/pin)
Storage Temperature
Max
–0.5 to +4.6
–0.5 to +5.5
–0.5 to +5.5
–3
120
–65 to +150
Unit
V
V
V
V
mA
°C
V
BIAS
A
0
A
1
A
2
A
3
A
4
A
5
GND
A
6
A
7
A
8
A
9
A
10
A
11
V
CC
A
12
GND
A
13
A
14
A
15
A
16
A
17
A
18
A
19
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
OE1
OE2
B
0
B
1
B
2
B
3
B
4
GND
B
5
B
6
B
7
B
8
B
9
B
10
B
11
B
12
GND
B
13
B
14
B
15
B
16
B
17
B
18
B
19
V
AC
I
OUT
T
STG
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
.
CAPACITANCE
(T
A
= +25°C, F = 1MHz, V
IN
= 0V, V
OUT
= 0V)
Symbol
C
IN
C
I/O
C
I/O
Parameter
(1)
Control Inputs
Quickswitch Channels (Switch OFF)
V
BIAS
= OPEN
Quickswitch Channels (Switch ON)
8
12
pF
NOTE:
1. This parameter is guaranteed but not production tested.
Typ.
3
4
Max.
5
6
Unit
pF
pF
PIN DESCRIPTION
Pin Names
OEx
V
BIAS
Ax
Bx
I/O
I
I
I/O
I/O
Description
Bus Switch Enable
Bias Voltage
Bus A
Bus B
FUNCTION TABLE
(EACH 10-BIT BUS SWITCH)
(1)
OEx
L
H
Bx
Ax
V
BIAS
Function
Connect
Disconnect Ax = Z
TSSOP
TOP VIEW
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
Z = High-Impedence
2
IDTQS3VH16800
2.5V / 3.3V 20-BIT HIGH BANDWIDTH BUS SWITCH WITH PRECHARGED OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= –40°C to +85°C, V
CC
= 3.3V ±0.3V
Symbol
V
IH
V
IL
V
BIAS
| I
O
|
I
IN
I
OZ
I
OFF
R
ON
Parameter
Input HIGH Voltage
Input LOW Voltage
Bias Voltage
Bias Current
(2)
Input Leakage Current (Control Inputs)
Off-State Current (Hi-Z)
Data Input/Output Power Off Leakage
Switch ON Resistance
for Control Inputs
Guaranteed Logic LOW
for Control Inputs
V
CC
= 3.3V to 3.6V, I
O
= 0
V
CC
= 2.3V to 2.7V, I
O
= 0
V
CC
= 3.3V, V
BIAS
= 2.4V, V
O
= 0,
OEx
= HIGH
0V
≤
V
IN
≤
V
CC
0V
≤
V
OUT
≤
5V, Switches OFF
V
IN
or V
OUT
0V to 5V, V
CC
= 0V
V
CC
= 2.3V
Typ. at V
CC
= 2.5V
V
CC
= 3V
NOTES:
1. Typical values are at V
CC
= 3.3V and T
A
= 25°C.
2. Bias resistance is 5KΩ typical at V
CC
= 3.3V; V
BIAS
= 2.4V at 25°C.
Test Conditions
Guaranteed Logic HIGH
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
V
CC
= 2.3V to 2.7V
V
CC
= 2.7V to 3.6V
Min.
1.7
2
—
—
0
0
0.25
—
—
—
I
ON
= 30mA
I
ON
= 15mA
I
ON
= 30mA
I
ON
= 15mA
—
—
—
—
Typ.
(1)
—
—
—
—
—
—
—
—
—
—
6
7
4
5
Max.
—
—
0.7
0.8
5
3.3
—
±1
±1
±1
8
9
6
8
Unit
V
V
V
mA
µA
µA
µA
Ω
V
IN
= 0V
V
IN
= 1.7V
V
IN
= 0V
V
IN
= 2.4V
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 3.3V
16
14
R
ON
(ohms)
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
4.5
5.0
V
IN
(Volts)
3
IDTQS3VH16800
2.5V / 3.3V 20-BIT HIGH BANDWIDTH BUS SWITCH WITH PRECHARGED OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
Symbol
I
CCQ
ΔI
CC
I
CCD
Parameter
Quiescent Power Supply Current
Power Supply Current
(2,3)
per Input HIGH
Dynamic Power Supply Current
(4)
Test Conditions
(1)
V
CC
= Max., V
IN
= GND or V
CC
, f = 0
V
CC
= Max., V
IN
= 3V, f = 0 per Control Input
V
CC
= 3.3V, A and B Pins Open, Control Inputs
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
ΔIcc.
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.
Min.
—
—
Typ.
1.5
—
Max.
3
30
Unit
mA
µA
See Typical I
CCD
vs Enable Frequency graph below
TYPICAL I
CCD
vs ENABLE FREQUENCY CURVE AT V
CC
= 3.3V
20
18
16
14
12
10
I
CCD
(mA)
8
6
4
2
0
0
2
4
6
8
10
12
14
16
18
20
ENABLE FREQUENCY (MHz)
4
IDTQS3VH16800
2.5V / 3.3V 20-BIT HIGH BANDWIDTH BUS SWITCH WITH PRECHARGED OUTPUTS
INDUSTRIAL TEMPERATURE RANGE
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
T
A
= -40°C to +85°C
V
CC
= 2.5 ± 0.2V
(1)
Symbol
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
f
OEx
Parameter
Data Propagation Delay
(2,3)
Ax to Bx or Bx to Ax
Switch Turn-On Delay
OEx
to Ax/Bx
Switch Turn-Off Delay
OEx
to Ax/Bx
Operating Frequency - Enable
(2,5)
(OEx)
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.