Enhanced N channel FET with no inherent diode to V
CC
Low propagation delay and zero ground bounce
25Ω resistors for low noise
Ω
Undershoot Clamp Diodes on all switch and control Inputs
Four enables control five bits each
TTL-compatible input and output levels
Available in 48-pin QVSOP package
DESCRIPTION:
APPLICATIONS:
•
•
•
•
•
•
The QS32X2384 provides a set of twenty high-speed CMOS TTL-
compatible bus switches. The QS32x2384 also includes internal 25Ω
series termination resistors to reduce reflection noise in high-speed
applications. The Bus Enable (BE) signals turn the switches on. Four Bus
Enable signals are provided, one for each of five bits of the 20-bit bus. The
‘384 family of QuickSwitch products is ideal for switching wide digital buses,
as well as hotplug buffering, and 5V to 3V conversion.
The QS32X2384 is characterized for operation at -40°C to +85°C.
Hot-swapping, hot-docking
Voltage translation (5V to 3.3V)
Power conservation
Capacitance reduction and isolation
Bus isolation
Clock gating
FUNCTIONAL BLOCK DIAGRAM
A
0
B
0
A
10
B
10
A
4
A
5
B
4
B
5
A
14
A
15
B
14
B
15
A
9
B
9
A
19
B
19
BEA
BEC
BED
BEB
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
INDUSTRIAL TEMPERATURE RANGE
c
2002 Integrated Device Technology, Inc.
APRIL 2002
1
DSC-5725/1
IDTQS32X2384
HIGH-SPEED CMOS 20-BIT BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Description
Max
V
TERM
(2)
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)
Maximum Power Dissipation (T
A
= 85°C)
Storage Temperature
–0.5 to +7
–0.5 to +7
–0.5 to +7
–3
120
0.5
–65 to +150
V
TERM
(3)
V
TERM
(3)
V
AC
I
OUT
P
MAX
T
STG
Unit
V
V
V
V
mA
W
°C
BEA
B
0
A
0
A
1
B
1
B
2
A
2
A
3
B
3
B
4
A
4
GND
BEC
B
5
A
5
A
6
B
6
B
7
A
7
A
8
B
8
B
9
A
9
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
QVSOP
TOP VIEW
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
V
CC
B
19
A
19
A
18
B
18
B
17
A
17
A
16
B
16
B
15
A
15
BEB
V
CC
B
14
A
14
A
13
B
13
B
12
A
12
A
11
B
11
B
10
A
10
BED
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)
Pins
Control Inputs
Quickswitch Channels (Switch OFF)
NOTE:
1. This parameter is guaranteed but not production tested.
Typ.
3
5
Max.
(1)
5
7
Unit
pF
pF
FUNCTION TABLE
(1)
BEA
H
L
H
L
BEC
H
L
H
L
BEB
H
H
L
L
BED
H
H
L
L
B
0
- B
4
Z
A
0
- A
4
Z
A
0
- A
4
B
5
- B
9
Z
A
5
- A
9
Z
A
5
- A
9
B
15
- B
19
Z
Z
A
15
- A
19
A
15
- A
19
B
10
- B
14
Z
Z
A
10
- A
14
A
10
- A
14
Function
Disconnect
Connect
Connect
Connect
Function
Disconnect
Connect
Connect
Connect
PIN DESCRIPTION
Pin Names
A
0
- A
19
B
0
- B
19
BEA
BEB
BEC
BED
I/O
I/O
I/O
I
I
I
I
Bus A
Bus B
Enable,
0 - 4
Enable,
15 - 19
Enable,
5 - 9
Enable,
10 - 14
Description
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't care
Z = High-Impedence
2
IDTQS32X2384
HIGH-SPEED CMOS 20-BIT BUS SWITCH
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
= 5.0V ± 5%
Symbol
V
IH
V
IL
I
IN
I
OZ
R
ON
V
P
Parameter
Input HIGH Voltage
Input LOW Voltage
Input Leakage Current (Control Inputs)
Off-State Current (Hi-Z)
Switch ON Resistance
(2)
Pass Voltage
(3)
Test Conditions
Guaranteed Logic HIGH for Control Pins
Guaranteed Logic LOW for Control Pins
0V
≤
V
IN
≤
V
CC
0V
≤
V
OUT
≤
V
CC
, Switches OFF
V
CC
= Min., V
IN
= 0V, I
ON
= 30mA
V
CC
= Min., V
IN
= 2.4V, I
ON
= 15mA
V
CC
= 5V, I
OUT
= -5µA
Min.
2
—
—
—
20
20
3.7
Typ.
(1)
—
—
±0.01
±0.01
28
35
4
Max.
—
0.8
±1
±1
40
48
4.2
V
Unit
V
V
µA
µA
Ω
NOTES:
1. Typical values are at V
CC
= 5.0V and T
A
= 25°C.
2. Max value of R
ON
is guaranteed but not production tested.
3. Pass voltage is guaranteed but not production tested.
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 5V
80
70
R
ON
(ohms)
60
50
40
30
20
10
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
V
IN
(Volts)
3
IDTQS32X2384
HIGH-SPEED CMOS 20-BIT BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
Symbol
I
CCQ
∆I
CC
I
CCD
Parameter
Quiescent Power Supply Current
Power Supply Current per Input HIGH
(2)
Dynamic Power Supply Current per
MHz
(3)
Test Conditions
(1)
V
CC
= Max., V
IN
= GND or V
CC
, f = 0
V
CC
= Max., V
IN
= 3.4V, f = 0
V
CC
= Max., A and B Pins Open
Control Input Toggling @ 50% Duty Cycle
NOTES:
1. For conditions shown as Min. or Max., use the appropriate values specified under DC Electrical Characteristics.
2. Per TTL driven input (V
IN
= 3.4V, control inputs only). A and B pins do not contribute to
∆Icc.
3. This current applies to the control inputs only and represents the current required to switch internal capacitance at the specified frequency. The A and B inputs generate no significant
AC or DC currents as they transition. This parameter is guaranteed but not production tested.
Max.
3
2.5
0.25
Unit
mA
mA
mA/MHz
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
T
A
= -40°C to +85°C
Symbol
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
Parameter
Data Propagation Delay
(2,4)
Ax to Bx, Bx to Ax
Switch Turn-On Delay
BEx
to Ax, Bx
Switch Turn-Off Delay
(2)
BEx
to Ax, Bx
Min.
(1)
1.5
1.5
Typ.
Max.
1.25
(3)
7.5
5.5
Unit
ns
ns
ns
NOTES:
1. Minimums are guaranteed but not production tested.
2. This parameter is guaranteed but not production tested.
3. The time constant for the switch alone is of the order of 1.25ns at C
L
= 50pF.
4. The bus switch contributes no propagation delay other than the RC delay of the ON resistance of the switch and the load capacitance. 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.
