PI3B3257A
3.3V, Quad 2:1 Mux/DeMux
NanoSwitch
™
Features
• Near-Zero propagation delay
• 5Ω switches connect inputs to outputs
• Fast Switching Speed: 4.8ns max.
• Ultra-Low Quiescent Power: 0.1µA typical
– Ideally suited for notebook applications
• Pin compatible with 74 series 257 logic devices
• Packaging (Pb-free & Green avaliable):
– 16-pin 150 mil wide plastic QSOP (Q)
Description
Pericom Semiconductor’s PI3B3257A is a 3.3 volt, Quad 2:1
multiplexer/demultiplexer with three-state outputs that is pinout
and function compatible with the PI74FCT257T, 74F257, and
74ALS/AS/LS257. Inputs can be connected to outputs with low
On-Resistance (5Ω) with no additional ground bounce noise or
propagation delay.
Block Diagram
I
A
0
I
A
1
I
B
0
I
B
1
I
C
0
Pin Configuration
I
C
1
I
D
0
I
D
1
½
½
½
½
½
½
½
½
½
½
½
½
½½
½½
½½
½½
½½
½½
½½
½
½
½½
½½
½
½
½
½
½
½
SW
SW
½
½
½
E
SW
½
½
SW
SW
½
½
½½
½
½
½
½
½
½
½
½
S
SW
SW
SW
½
½
½
½
½½
½½½
SW
½
½½
Y
A
Y
B
Y
C
Y
D
I
Y
Pin Description
Pin Name
I
A
N
-
I
D
N
E
Description
Data Inputs
Select Inputs
Enable
Data Outputs
Ground
Power
No Connect
Truth Table
(1)
E
H
L
L
S
X
L
H
Y
A
Hi-Z
I
A
0
I
A
1
S
Y
B
Hi-Z
I
B
0
I
B
1
Y
C
Hi-Z
I
C
0
I
C
1
Y
D
Hi-Z
I
D
0
I
D
1
Function
Disable
S=0
S=1
E
Y
A
-Y
D
GND
V
CC
NC
Note:
1. H = High Voltage Level
L = Low Voltage Level
06-0220
1
PS8758B
05/16/06
PI3B3257A
3.3V, Quad 2:1 Mux/DeMux
NanoSwitch
™
Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
Storage Temperature ..................................................................... –65°C to +150°C
Ambient Temperature with Power Applied .................................... –40°C to +85°C
Supply Voltage to Ground Potential................................................. –0.5V to +4.6V
DC Input Voltage ............................................................................. –0.5V to +4.6V
DC Output Current........................................................................................ 120mA
Power Dissipation ............................................................................................ 0.5W
Note:
Stresses greater than those listed under 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.
DC Electrical Characteristics
(Over the Operating Range, T
A
= –40°C to +85°C, V
CC
= 3.3V ±10%)
Parameters
V
IH
V
IL
I
IH
I
IL
I
OZH
V
IK
R
ON
Description
Input HIGH Voltage
Input LOW Voltage
Input HIGH Current
Input LOW Current
High Impedance Output Current
Clamp Diode Voltage
Switch On-Resistance
(3)
Test Conditions
(1)
Min.
2
–0.5
Guaranteed Logic HIGH Level
Guaranteed Logic LOW Level
V
CC
= Max., V
IN
= V
CC
V
CC
= Max., V
IN
= GND
0 ≤ In, Yn ≤ V
CC
V
CC
= Min., I
IN
= –18mA
V
CC
= Min., V
IN
= 0.0V,
Ion = 48mA or 64mA
V
CC
= Min., V
IN
= 2.4V, I
ON
= 15mA
Typ.
(2)
Max. Units
0.8
±1
±1
±1
–1.2
V
Ω
µA
V
5
8
7
17
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 3.3V,
T
A
= 25°C ambient and maximum loading.
3. Measured by the voltage drop between I and Y pin at indicated current through the switch. On-Resistance is determined by the lower of the
voltages on the two (I,Y) pins.
Capacitance
(T
A
= 25°C, f = 1 MHz)
Parameters
(1)
C
IN
C
OFFYN
C
OFFIN
C
ON
Description
Input Capacitance
Y
N
Capacitance, Switch OFF
I
N
Capacitance, Switch OFF
I
N
/Y
N
Capacitance, Switch ON
V
IN
= 0V
Test Conditions
Typical
2
7.5
4.0
11
pF
Units
Notes:
1. This parameter is determined by device characterization but is not production tested.
06-0220
2
PS8758B
05/16/06
PI3B3257A
3.3V, Quad 2:1 Mux/DeMux
NanoSwitch
™
Power Supply Characteristics
Parameters
I
CC
∆I
CC
Description
Quiescent Power Supply Current
Supply Current per Input @ TTL
HIGH
(3, 4)
V
CC
= Max.
V
CC
= Max.
Test Conditions
(1)
V
IN
= GND or V
CC
V
IN
= 3.0
Min.
Typ.
(2)
0.1
Max. Units
3.0
750
µA
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device.
2. Typical values are at V
CC
= 3.3V, +25°C ambient.
3. Per TTL driven input (control inputs only); I and Y pins do not contribute to I
CC
.
4. This current applies to the control inputs only and represent the current required to switch internal capacitance at the specified frequency. The I
and Y inputs generate no significant AC or DC currents as they transition. This parameter is not tested, but is guaranteed by design.
Switching Characteristics Over Operating Range
Parameters
t
IY
t
SY
t
PZH
t
PZL
t
PHZ
t
PLZ
Description
Propagation Delay In to Yn
(1,2)
Bus Select Time, Sn to Yn
Bus Enable Time, E to Yn
Bus Disable Time, E to Yn
C
L
= 50pF
R
L
= 500Ω
1
1
1
Conditions
Com.
Min.
Max.
0.25
4.5
4.5
4.8
ns
Units
Notes:
1. This parameter is guaranteed but not tested on Propagation Delays.
2. The bus switch contributes no propagational delay other than the RC delay of the On-Resistance of the switch and the load capacitance. The
switch’s time constant alone is of the order of 0.25ns for 50pF load. Since this time constant is much smaller than the rise/fall times of typical
driving signals, it adds very little propagational delay to the system. Propagational 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.
Applications Information
Logic Inputs
The logic control inputs can be driven up to +3.6V regardless of the supply voltage. For example, given a + 3.3V supply, IN may be
driven low to 0V and high to 3.6V. Driving IN Rail-to-Rail
®
minimizes power consumption.
Power-Supply Sequencing and Hot-Plug Information
Proper power-supply sequencing is recommended for all CMOS devices. Always apply V
CC
and GND before applying signals to
input/output or control pins.
Rail-to-Rail is a registeredtrademark of Nippon Motorola, Ltd.
06-0220
3
PS8758B
05/16/06
PI3B3257A
3.3V, Quad 2:1 Mux/DeMux
NanoSwitch
™
Packaging Mechanical: 16-Pin QSOP (Q)
16
.008
0.20
MIN.
.150
.157
3.81
3.99
.008
.013
0.20
0.33
Guage Plane
.010
0.254
1
.189
.197
4.80
5.00
Detail A
.016
.035
0.41
0.89
.041
1.04
REF
0˚-6˚
.015 x 45°
0.38
.053
1.35
.069
1.75
Detail A
.008
0.203
REF
.007
.010
0.178
0.254
SEATING
PLANE
.004
0.101
.010
0.254
0.41
.016
1.27
.050
.228
.244
5.79
6.19
.025
BSC
0.635
.008
.012
0.203
0.305
X.XX
DENOTES DIMENSIONS IN MILLIMETERS
X.XX
Ordering Information
Ordering Code
PI3B3257AQ
PI3B3257AQE
Packaging Code
Q
Q
Package Description
16-pin 150-mil wide plastic QSOP
Pb-Free & Green, 16-pin 150-mil wide plastic QSOP
Notes:
•
Thermal characteristics can be found on the company web site at www.pericom.com/packaging/
•
E = Pb-free & Green
• Adding an
X suffix = Tape/Reel
Pericom Semiconductor Corporation • 1-800-435-2336 • www.pericom.com
06-0220
4
PS8758B
05/16/06
京公网安备 11010802033920号
EEWORLD
