1PS8151K 05/16/06
Pin Description
Pin Name Description
IAN-IDNData Inputs
S Select Inputs
E Enable
YA-YDData Outputs
GND Ground
VCC Power
NC No Connect
Description
Pericom Semiconductor’s PI3B3257 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
PI3B3257
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)
– 16-pin 150 mil wide plastic SOIC (W)
– 16-pin 173 mil wide plastic TSSOP (L)
Pin Conguration
Note:
1. H = High Voltage Level
L = Low Voltage Level
E
IA0I
A
1
I
B
0I
B
1I
C
0I
C
1I
D
0I
D
1
S
YAY
B
YCYD
I Y
E
SW
SW
SW
SW
SW
SW
SW
SW
SW
Truth Table(1)
E S YAYBYCYDFunction
H X Hi-Z Hi-Z Hi-Z Hi-Z Disable
L L IA0 IB0 IC0 ID0S = 0
L H IA1 IB1 IC1 ID1S = 1
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2PS8151K 05/16/06
PI3B3257
3.3V, Quad 2:1
Mux/DeMux NanoSwitch™
Notes:
1. This parameter is determined by device characterization but is not production 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 specication is not
mplied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
DC Electrical Characteristics (Over the Operating Range, TA = –40°C to +85°C, VCC = 3.3V ±10%)
Parameters Description Test Conditions(1) Min. Typ.(2) Max. Units
VIH Input HIGH Voltage Guaranteed Logic HIGH Level 2 V
VIL Input LOW Voltage Guaranteed Logic LOW Level –0.5 0.8
IIH Input HIGH Current VCC = Max., VIN = VCC ±1
µAIIL Input LOW Current VCC = Max., VIN = GND ±1
IOZH High Impedance Output Current 0 ≤ In, Yn ≤ VCC ±1
VIK Clamp Diode Voltage VCC = Min., IIN = –18mA –1.2 V
RON Switch On-Resistance(3)
VCC = Min., VIN = 0.0V,
Ion = 48mA or 64mA 5 8 Ω
VCC = Min., VIN = 2.4V, ION = 15mA 8 17
Capacitance (TA = 25°C, f = 1 MHz)
Parameters(1) Description Test Conditions Typ. Units
CIN Input Capacitance
VIN = 0V
3.0
pF
COFFYN YN Capacitance, Switch OFF 17.0
COFFIN IN Capacitance, Switch OFF 8.5
CON IN/YN Capacitance, Switch ON 25
Notes:
1. For Max. or Min. conditions, use appropriate value specied under Electrical Characteristics for the applicable device type.
2. Typical values are at VCC = 3.3V, TA = 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.
06-0220
3PS8151K 05/16/06
PI3B3257
3.3V, Quad 2:1
Mux/DeMux NanoSwitch™
Notes:
1. For Max. or Min. conditions, use appropriate value specied under Electrical Characteristics for the applicable device.
2. Typical values are at VCC = 3.3V, +25°C ambient.
3. Per TTL driven input (control inputs only); I and Y pins do not contribute to ICC.
4. This current applies to the control inputs only and represent the current required to switch internal capacitance at the specied frequency. The I
and Y inputs generate no signicant AC or DC currents as they transition. This parameter is not tested, but is guaranteed by design.
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.
Power Supply Characteristics
Parameters Description Test Conditions(1) Min. Typ.(2) Max. Units
ICC Quiescent Power Supply Current VCC = Max. VIN = GND or VCC 0.1 3.0
µA
∆ICC Supply Current per Input @ TTL
HIGH(3, 4) VCC = Max. VIN = 3.0 750
Switching Characteristics Over Operating Range
Parameters Description Conditions
PI3B3257
UnitsCom.
Min. Max.
tIY Propagation Delay In to Yn(1,2)
CL = 50pF
RL = 500Ω
0.25
ns
tSY Bus Select Time, Sn to Yn 1 4.5
tPZH
tPZL Bus Enable Time, E to Yn 1 4.5
tPHZ
tPLZ Bus Disable Time, E to Yn 1 4.8
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4PS8151K 05/16/06
PI3B3257
3.3V, Quad 2:1
Mux/DeMux NanoSwitch™
.189
.197
.053
.069
.004
.010
SEATING
PLANE
.025
BSC
.007
.010
.228
.244
1
16
.150
.157
.016
.050
X.XX
X.XX DENOTES DIMENSIONS IN MILLIMETERS
0.635
4.80
5.00
1.35
1.75
5.79
6.19
0.101
0.254
.008
.012
0.203
0.305
3.81
3.99
0.178
0.254
0.38
0.41
1.27
.008
0.203
.015 x 45°
REF
Detail A
Detail A
.008
0.20
MIN.
Guage Plane
.010
0.254
.041
1.04
REF
.016
.035
0.41
0.89
0˚-6˚
.008
.013
0.20
0.33
SEATING PLANE
.050
BSC
1
16
0-8˚
.149
.157
X.XX
X.XX
DENOTES DIMENSIONS
IN MILLIMETERS
3.78
3.99
.386
.393
9.80
10.00
1.27
.053
.068
1.35
1.75
.2284
.2440
5.80
6.20
.0040
.0098
0.10
0.25
.013
.020
.0155
.0260
0.330
0.508
0.393
0.660
.0075
.0098
0.25
0.50
.0099
.0196
x 45˚
0.19
0.25
.016
.050
0.41
1.27
REF
Packaging Mechanical: 16-Pin QSOP (Q)
Packaging Mechanical: 16-Pin SOIC (W)
06-0220
5PS8151K 05/16/06
PI3B3257
3.3V, Quad 2:1
Mux/DeMux NanoSwitch™
.193
.201
.047
max.
.002
.006
SEATING
PLANE
.0256
BSC
.018
.030
.004
.008
.252
BSC
1
16
.169
.177
0.05
0.15
6.4
0.45
0.75
0.09
0.20
4.3
4.5
1.20
4.9
5.1
0.65 0.19
0.30
.007
.012
Packaging Mechanical: 16-Pin TSSOP (L)
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 VCC and GND before applying signals to
input/output or control pins.
Rail-to-Rail is a registeredtrademark of Nippon Motorola, Ltd.
Ordering Information
Ordering Code Packaging Code Package Description
PI3B3257Q Q 16-pin 150 mil wide plastic QSOP
PI3B3257QE Q Pb-Free & Green, 16-pin 150 mil wide plastic QSOP
PI3B3257W W 16-pin 150-mil wide plastic SOIC
PI3B3257WE W Pb-Free & Green, 16-pin 150-mil wide plastic SOIC
PI3B3257L L 16-pin 173-mil wide plastic TSSOP
PI3B3257LE L Pb-Free & Green, 16-pin 173 mil wide plastic TSSOP
Notes:
• Thermal characteristics can be found on the company web site at www.pericom.com/packaging/
• E = Pb-free & Green
• Adding an X sufx = Tape/Reel
Pericom Semiconductor Corporation • 1-800-435-2336 • www.pericom.com
06-0220
