Fairchild FSTU3257MTC Quad 2:1 multiplexer/demultiplexer bus switch with 2v undershoot protection Datasheet

Revised October 2006
FSTU3257
Quad 2:1 Multiplexer/Demultiplexer Bus Switch with
2V Undershoot Protection
General Description
Features
The Fairchild Switch FSTU3257 is a quad 2:1 high-speed
CMOS TTL-compatible multiplexer/demultiplexer bus
switch. The low on resistance of the switch allows inputs to
be connected to outputs without adding propagation delay
or generating additional ground bounce noise.
■ Undershoot hardened to 2V (A and B Ports)
When OE is LOW, the select pin connects the A Port to the
selected B Port output. The A and B Ports are “undershoot
hardened” with Undershoot Hardened Circuit (UHC®¥) protection to support an extended range of 2.0V below
ground. Fairchild’s integrated UHC senses undershoot at
the I/O and responds by preventing voltage differentials
from developing and turning on the switch. When OE is
HIGH, the switch is OPEN and a high-impedance state
exists between the two ports.
■ Soft enable turn-on to minimize bus to bus charge
sharing during enable
■ 4: switch connection between two ports.
■ Minimal propagation delay through the switch.
■ Low lCC.
■ Zero bounce in flow-through mode.
■ Control inputs compatible with TTL level.
■ See Applications Note AN-5008 for details
Ordering Code:
Order Number
Package Number
FSTU3257M
M16A
Package Description
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow
FSTU3257QSC
MQA16
16-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150" Wide
FSTU3257MTC
MTC16
16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.
Logic Diagram
Connection Diagram
Pin Descriptions
Truth Table
Pin Name
Description
S
OE
Function
OE
Bus Switch Enable
X
H
Disconnect
S
Select Input
L
L
A
B1
A
Bus A
H
L
A
B2
B1–B2
Bus B
UHC®¥ is a registered trademark of Fairchild Semiconductor Corporation.
© 2005 Fairchild Semiconductor Corporation
DS500302
www.fairchildsemi.com
FSTU3257 Quad 2:1 Multiplexer/Demultiplexer Bus Switch with 2V Undershoot Protection
August 1999
FSTU3257
Absolute Maximum Ratings(Note 1)
Recommended Operating
Conditions (Note 4)
0.5V to 7.0V
2.0V to 7.0V
0.5V to 7.0V
50mA
Supply Voltage (VCC)
DC Switch Voltage (VS) (Note 2)
DC Input Control Pin Voltage (VIN)(Note 3)
DC Input Diode Current (lIK) VIN 0V
DC Output (IOUT)
Power Supply Operating (VCC)
128mA
DC VCC/GND Current (ICC/IGND)
Storage Temperature Range (TSTG)
4.0V to 5.5V
Input Voltage (VIN)
0V to 5.5V
Output Voltage (VOUT)
0V to 5.5V
Input Rise and Fall Time (tr, tf)
/ 100mA
65qC to 150 qC
Switch Control Input
0nS/V to 5nS/V
Switch I/O
ESD
0nS/V to DC
40 qC to 85 qC
Free Air Operating Temperature (TA)
Human Body Model
5kV
Note 1: The Absolute Maximum Ratings are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum rating.
The Recommended Operating Conditions tables will define the conditions
for actual device operation.
Note 2: VS is the voltage observed/applied at either the A or B Ports across
the switch.
Note 3: The input and output negative voltage ratings may be exceeded if
the input and output diode current ratings are observed.
Note 4: Unused control inputs must be held HIGH or LOW. They may not
float.
DC Electrical Characteristics
VCC
Symbol
Parameter
(V)
40 qC to 85 qC
TA
Min
Typ
(Note 5)
Max
1.2
Units
Conditions
18mA
VIK
Clamp Diode Voltage
VIH
HIGH Level Input Voltage
4.0–5.5
VIL
LOW Level Input Voltage
4.0–5.5
0.8
V
II
Input Leakage Current
5.5
r1.0
PA
0d VIN d5.5V
IOZ
OFF-STATE Leakage Current
5.5
r1.0
PA
0 dA, B dVCC
RON
Switch On Resistance
4.5
4
7
:
VIN
0V, IIN
64mA
(Note 6)
4.5
4
7
:
VIN
0V, IIN
30mA
4.5
8
15
:
VIN
2.4V, IIN
15mA
4.0
11
20
:
VIN
2.4V, IIN
15mA
VCC or GND, IOUT
4.5
2.0
V
IIN
V
ICC
Quiescent Supply Current
5.5
3
PA
VIN
' ICC
Increase in ICC per Input
5.5
2.5
mA
One input at 3.4V
VIKU
Voltage Undershoot
5.5
2.0
V
0
Other inputs at VCC or GND
0.0 mA t IIN t 50 mA
OE
Note 5: Typical values are at VCC
5.0V and T A
5.5V
25qC
Note 6: Measured by the voltage drop between A and B pins at the indicated current through the switch. On resistance is determined by the lower of the
voltages on the two (A or B) pins.
www.fairchildsemi.com
2
TA
Symbol
CL
Parameter
VCC
4.5 – 5.5V
Min
tPHL,tPLH
Max
Prop Delay Bus to Bus (Note 7)
Prop Delay, Select to Bus A
40 qC to 85qC,
50pF, RU
7.0
RD
500:
VCC
Min
Units
No.
0.25
0.25
30.0
35.0
7.0
30.0
35.0
Output Enable Time, OE to Bus A, B
7.0
30.0
35.0
ns
ns
1.5
8.4
9.8
1.5
8.8
9.8
ns
Output Disable Time, Output Enable Time, OE to Bus A, B
Figure
Max
tPZH, tPZL Output Enable Time, Select to Bus B
tPHZ, tPLZ Output Disable Time, Select to Bus B
Conditions
4.0V
VI
OPEN
Figures
2, 3
VI
7V for tPZL
VI
OPEN for tPZH
VI
7V for tPLZ
VI
OPEN for tPHZ
Figures
2, 3
Figures
2, 3
Note 7: This parameter is guaranteed by design but is not tested. The bus switch contributes no propagation delay other than the RC delay of the typical On
resistance of the switch and the 50pF load capacitance, when driven by an ideal voltage the source (zero output impedance).
Capacitance
(Note 8)
Symbol
Parameter
Typ
Control Pin Input Capacitance
CIN
A Port
CI/O
B Port
CI/O ON State
Note 8: TA
Input/Output Capacitance
Input/Output Capacitance ON State (A or B Port)
25qC, f
Max
3
Units
pF
7.5
pF
5.5
pF
14
pF
Conditions
VCC
5.0V
VCC, OE
VCC
5.0V
5.0V Switch ON
1 MHz, Capacitance is characterized but not tested.
Undershoot Characteristic (Note 9)
Symbol
Parameter
Output Voltage During Undershoot
VOUTU
Min
Typ
2.5
VOH 0.3
Max
Units
Conditions
V
Figure 1
Note 9: This is intended to characterize the device’s protective capabilities by maintaining output signal integrity during an input transient voltage undershoot
event.
FIGURE 1.
Device Test Conditions
Parameter
Value
VIN
See Waveform
V
R1 - R2
100K
:
VTRI
11.0
V
VCC
5.5
V
Transient
Input Voltage (VIN) Waveform
Units
3
www.fairchildsemi.com
FSTU3257
AC Electrical Characteristics
FSTU3257
AC Loading and Waveforms
Note: Input driven by 50: source terminated in 50:
Note: CL includes load and stray capacitance
Note: Input PRR
1.0 MHz, tW
500 ns
FIGURE 2. AC Test Circuit
FIGURE 3. AC Waveforms
www.fairchildsemi.com
4
FSTU3257
Physical Dimensions inches (millimeters) unless otherwise noted
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow
Package Number M16A
16-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150" Wide
Package Number MQA16
5
www.fairchildsemi.com
FSTU3257 Quad 2:1 Multiplexer/Demultiplexer Bus Switch with 2V Undershoot Protection
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Package Number MTC16
Technology Description
The Fairchild Switch family derives from and embodies Fairchild’s proven switch technology used for several years in its
74LVX3L384 (FST3384) bus switch product.
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
www.fairchildsemi.com
www.fairchildsemi.com
6
Similar pages