IDT IDTQS3V245SO

IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH® PRODUCTS
3.3V HIGH SPEED BUS SWITCH
FEATURES:
DESCRIPTION:
5Ω
Ω bi-directional switches connect inputs to outputs
Pin compatibility with QS3245
250ps propagation delay
Undershoot Clamp Diodes on all switch and control Inputs
LVTTL-compatible control Inputs
Available in SOIC and QSOP packages
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•
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IDTQS3V245
The QS3V245 is an 8-bit high speed bus switch controlled by LVTTLcompatible active low enable signal. When closed, the switches exhibit near
zero propagation delay without generating additional ground bounce or
switching noise.
The QS3V245 is specially designed for direct interface between 3.3V and
2.5V devices without any external components. When operating from a 3.3V
supply, the logic high level at the switch output is clamped to 2.5V when the
switch input signal exceeds 2.5V. This device can be used for switching 2.5V
buses without signal attenuation. The ON resistance at 3.3V VCC is less than
5Ω typical, providing near zero propagation delay through the switch.
Absence of DC path from switch I/O pins to VCC or ground makes QS3V245
an ideal device for hot swapping applications.
The QS3V245 is characterized for operation from -40°C to +85°C.
APPLICATIONS:
• 3.3V to 2.5V voltage translation
• 2.5V to 1.8V voltage translation
• PCI bus isolation hot swap
FUNCTIONAL BLOCK DIAGRAM
OE
2
3
4
5
6
7
8
9
A0
A1
A2
A3
A4
A5
A6
A7
B0
B1
B2
B3
B4
B5
B6
B7
18
17
16
15
14
13
12
11
19
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
NOVEMBER 2000
INDUSTRIAL TEMPERATURE RANGE
1
c
2000 Integrated Device Technology, Inc.
DSC-5512/1
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
ABSOLUTE MAXIMUM RATINGS(1)
PIN CONFIGURATION
NC
1
20
VCC
A0
2
19
OE
A1
3
18
B0
A2
4
17
B1
A3
5
16
B2
A4
6
15
B3
A5
7
14
B4
A6
8
13
B5
A7
9
12
B6
10
11
B7
GND
Symbol
Description
Max
Unit
VTERM(2)
Supply Voltage to Ground
–0.5 to +4.6
V
VS
DC Switch Voltage
–0.5 to +4.6
V
VIN
DC Input Voltage
–0.5 to +4.6
V
VAC
AC Input Voltage (pulse width ≤20ns)
–3
V
IOUT
DC Output Current (max. sink current/pin)
120
mA
Maximum Power Dissipation
TSTG
Storage Temperature
0.5
W
–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. VCC terminals.
CAPACITANCE (TA = +25°C, f = 1MHz, VIN = 0V, VOUT = 0V)
Parameter(1)
Symbol
SOIC/ QSOP
TOP VIEW
Typ.
Max.
Unit
CIN
Control Inputs
4
6
pF
CI/O
Quickswitch Channels (Switch OFF)
5
7
pF
NOTE:
1. As applicable to the device type.
PIN DESCRIPTION
Pin Names
Description
OE
Output Enable
Ax
Data I/Os
Bx
Data I/Os
FUNCTION TABLE(1)
OE
Outputs
H
Disconnected
L
Ax = Bx
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
2
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: TA = –40°C to +85°C, VCC = 3.3V ±0.3V
Symbol
Parameter
Test Conditions
Min.
Typ.(1) Max.
Unit
VIH
Input HIGH Voltage
Guaranteed Logic HIGH for Control Inputs
2
—
—
V
VIL
Input LOW Voltage
Guaranteed Logic LOW for Control Inputs
—
—
0.8
V
IIN
Input Leakage Current (Control Inputs)
0V ≤ VIN ≤ VCC
—
—
1
µA
IOZ
Off-State Current (Hi-Z)
0V ≤ VOUT ≤ VCC, Switches OFF
—
0.001
1
µA
VCC = Min., VIN = 0V, ION = 8mA
—
5
7
VCC = Min., VIN = 1.7V, ION = 8mA
—
15
20
VCC = 2.3V, VIN = 0V, ION = 8mA
—
7
—
RON
VP
Switch ON Resistance
Pass Voltage(2)
VCC = 2.3V, VIN = 1.3V, ION = 8mA
—
25
—
VIN = VCC = 3.3V, IOUT = -5µA
2.3
2.7
2.9
VIN = VCC = 2.5V, IOUT = -5µA
—
1.8
—
NOTES:
1. Typical values are at VCC = 3.3V and TA = 25°C.
2. Pass voltage is guaranteed, but not production tested.
TYPICAL ON RESISTANCE vs VIN AT VCC = 3.3V
16
14
12
10
R ON
(ohms)
8
6
4
2
0
0
0.5
1
1.5
V IN
(Volts)
3
2
2.5
Ω
V
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
TA = –40°C to +85°C, VCC = 3.3V ±0.3V
Symbol
Parameter
Test Conditions(1)
Min.
Max.
Unit
ICCQ
Quiescent Power Supply Current
VCC = Max., VIN = GND or VCC, f = 0
—
3
µA
∆ICC
Power Supply Current (2) per Input HIGH
VCC = Max., VIN = 3V or VCC, f = 0 per Control Input
—
30
µA
ICCD
Dynamic Power Supply Current per MHz (3)
VCC = 3.3V, A and B Pins Open, Control Input Toggling
—
0.15
mA/MHz
@ 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 (VIN = 3V, 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.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE(1)
TA = -40°C to +85°C
Symbol
Parameter
Min.
Typ.
Max.
Unit
tPLH
Data Propagation Delay(2,3)


0.25
ns
tPHL
Ax to/from Bx
0.5

6.5
ns
0.5

4
ns
tPZL
Switch Turn-On Delay
tPZH
OE to Ax/Bx
tPLZ
Switch Turn-Off Delay(2)
tPHZ
OE to Ax/Bx
NOTES:
1. See TEST CIRCUITS AND WAVEFORMS. Minimums 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 0.25ns for CL = 30pF. 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
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
OUTPUT VI CHARACTERISTICS
VOUT (Volts)
2
250
200
-100
IOs - (mA)
IOs - (mA)
1
-50
150
100
50
3
-150
-200
-250
0
-300
0
0.5
1
2
1.5
VOUT (Volts)
Outputs Low Characteristic
Outputs High Characteristic
PASS VOLTAGE vs VCC
V O UT - (Volts)
3
2.5
V OUT = 2.5V @ V CC = 3.3V
V O UT = 1.8V @ V CC = 2.5V
2
1.5
2.2
2.4
2.7
3
V CC (V)
5
3.3
3.6
4
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
3.3V TO 2.5V VOLTAGE TRANSLATION
3.3V
V OUT
3.3V Supply
2.5V
2.5V
Output of Switch
3.3V
QS3V245
2.5V
2.5V
V IN
0V
3.3V
Input of Switch
2.5V TO 1.8V VOLTAGE TRANSLATION
2.5V
V O UT
1.8V
1.8V
QS3V245
1.8V
1.8V
Output of Switch
2.5V
2.5V Supply
V IN
0V
2.5V
Input of Switch
6
IDTQS3V245
3.3V HIGH SPEED BUS SWITCH
INDUSTRIAL TEMPERATURE RANGE
ORDERING INFORMATION
IDTQS
XXXXX
Device Type
XX
Package
CORPORATE HEADQUARTERS
2975 Stender Way
Santa Clara, CA 95054
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Small Outline IC (Gull Wing)
Quarter Size Small Outline Package
3V245
3.3V High Speed Bus Switch
for SALES:
800-345-7015 or 408-727-6116
fax: 408-492-8674
www.idt.com
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[email protected]
(408) 654-6459