HIGH-SPEED CMOS QUICKSWITCH 8-BIT LOW RESISTANCE BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH
®
PRODUCTS
HIGH-SPEED CMOS
QUICKSWITCH 8-BIT LOW
RESISTANCE BUS SWITCH
FEATURES:
•
•
•
•
•
•
•
IDTQS3R245
DESCRIPTION:
Enhanced N channel FET with no inherent diode to Vcc
5Ω bidirectional switches connect inputs to outputs
Ω
Pin compatible with the 74F245, 74FCT245, and 74FCT245T
Zero propagation delay, zero ground bounce
Undershoot clamp diodes on all switch and control inputs
TTL-compatible control inputs
Available in SOIC and QSOP packages
APPLICATIONS:
The QS3R245 provides a set of eight high-speed CMOS TTL-compatible
bus switches in a pinout compatible with 74FCT245, 74F245, 74ALS/AS/
LS245 8-bit transceivers. The low ON resistance of the QS3R245 allows
inputs to be connected to outputs without adding propagation delay and
without generating additional ground bounce noise. The Output Enable (OE)
signal turns the switches on similar to the
OE
signal of the 74’245. The low
ON resistance of QS3R245 makes it ideal for PCI hot docking applications.
QuickSwitch devices provide an order of magnitude faster speed than
conventional logic devices.
The QS3R245 is characterized for operation at -40°C to +85°C.
• Hot-swapping and hot-docking (low resistance for PCI and
Compact PCI applications)
• Bus switching and isolation
• Voltage translation (5V to 3.3V)
• Capacitance reduction and isolation
• Power conservation
• Logic replacement (data processing)
• Clock gating
FUNCTIONAL BLOCK DIAGRAM
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
OE
B
0
B
1
B
2
B
3
B
4
B
5
B
6
B
7
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
INDUSTRIAL TEMPERATURE RANGE
1
c
1999 Integrated Device Technology, Inc.
NOVEMBER 1999
DSC-5546/1
IDTQS3R245
HIGH-SPEED CMOS QUICKSWITCH 8-BIT LOW RESISTANCE BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
TERM
(2)
Description
Supply Voltage to Ground
DC Switch Voltage Vs
DC Input Voltage V
IN
AC Input Voltage (pulse width
≤
20ns)
DC Output Current
Maximum Power Dissipation
Storage Temperature
Max
–0.5 to +7
–0.5 to +7
–0.5 to +7
–3
120
0.5
–65 to +150
Unit
V
V
V
V
mA
W
°C
V
TERM
(3)
V
TERM
(3)
V
AC
I
OUT
P
MAX
T
STG
NC
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
GND
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
CC
OE
B
0
B
1
B
2
B
3
B
4
B
5
B
6
B
7
NOTE:
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 terminals.
3. All terminals except Vcc.
CAPACITANCE
SOIC/ QSOP/ TSSOP
TOP VIEW
Pins
Control Pins
(T
A
= +25°C, f = 1.0MH
Z
, V
IN
= 0V, V
OUT
= 0V)
Typ.
3
5
Max.
(1)
4
6
Unit
pF
pF
Quickswitch Channels (Switch OFF)
NOTE:
1. This parameter is measured at characterization but not tested.
PIN DESCRIPTION
Pin Names
OE
Ax
Bx
Output Enable
Data I/Os
Data I/Os
Description
FUNCTION TABLE
(1)
OE
H
L
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
Outputs
Disconnected
Ax = Bx
2
IDTQS3R245
HIGH-SPEED CMOS QUICKSWITCH 8-BIT LOW RESISTANCE 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 ±10%
Symbol
V
IH
V
IL
I
IN
I
OZ
R
ON
V
P
Parameter
Input HIGH Level
Input LOW Level
Input LeakageCurrent (Control Inputs)
Off-State Output 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
IN
= V
CC
= 5V, I
OUT
= -5µA
Min.
2
—
—
—
—
—
3.7
Typ.
(1)
—
—
—
0.001
2.5
4
4
Max.
—
0.8
±1
±1
5
8.5
4.3
Unit
V
V
µA
µA
Ω
V
NOTES:
1. Typical values are at V
CC
= 5.0V, T
A
= 25°C.
2. Max value of R
ON
is guaranteed but not tested.
3. Pass Voltage is guaranteed but not production tested.
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 5V
16
R
ON
(ohms)
14
12
10
8
6
4
2
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
V
IN
(Volts)
3
IDTQS3R245
HIGH-SPEED CMOS QUICKSWITCH 8-BIT LOW RESISTANCE BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
Symbol
I
CCQ
∆I
CC
I
CCD
Parameter
Quiescent Power Supply Current
Power Supply Current per Control Input HIGH
(2)
Dynamic Power Supply Current per MHz
(3)
Test Conditions
(1)
V
CC
= Max., V
IN
= GND or Vcc, f = 0
V
CC
= Max., V
IN
= 3.4V, f = 0
V
CC
= Max., A and B pins open
Control Inputs Toggling at 50% Duty Cycle
NOTES:
1. For conditions shown as Min. or Max., use the appropriate values specified under DC Electrical Characteristics.
2. Per TLL 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
µA
mA
mA/MHz
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
T
A
= -40°C to +85°C, V
CC
= 5.0V ± 10%;
C
LOAD
= 50pF, R
LOAD
= 500Ω unless otherwise noted.
Symbol
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
Data Propagation Delay
(2,3)
An to/from Bn
Switch Turn-on Delay
OE
to Ax/Bx
Switch Turn-off Delay
(2)
OE
to Ax/Bx
0.5
—
4.5
ns
Parameter
Min.
(1)
—
0.5
Typ.
—
—
Max.
0.12
5.6
Unit
ns
ns
NOTES:
1.
Minimums are guaranteed but not production tested.
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 0.12ns for 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
IDTQS3R245
HIGH-SPEED CMOS QUICKSWITCH 8-BIT LOW RESISTANCE BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
ORDERING INFORMATION
IDTQS XXXXX
Device Type
XX
Package
X
Process
Blank
Industrial (-40°C to +85°C)
SO
Q
Small Outline IC
Quarter Size Outline Package
3R245
High Speed Quickswitch 8-Bit Low Resistance Bus Switch
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