The 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.
Pin Configuration
(UQFN)
V
CC
I
D
0
16
S
I
A
0
15
14
I
D
1
E
13
12
1
Y
D
I
C
0
I
C
1
2
3
11
10
Block Diagram
I
A
0
I
A
1 I
B
0
I
B
1 I
C
0
I
C
1 I
D
0
I
D
1
I
A
1
Y
A
4
5
I
B
0
9
6
I
B
1
Y
C
Y
B
SW
E
SW
SW
SW
S
SW
SW
SW
Transparent top view
Truth Table
(1)
E
H
L
SW
S
X
L
H
Y
A
Hi-Z
I
A
0
I
A
1
Y
B
Hi-Z
I
B
0
I
B
1
Y
C
Hi-Z
I
C
0
I
C
1
GND
SW
7
8
Y
D
Hi-Z
I
D
0
I
D
1
Function
Disable
S=0
S=1
Y
A
Y
B
Y
C
Y
D
I
Y
Note:
1. H = High Voltage Level
L = Low Voltage Level
L
Pin Description
E
Pin Name
I
A
N
-
I
D
N
Description
Data Inputs
Select Inputs
Enable
Data Outputs
Ground
(1)
Power
No Connect
Pin Configuration
(QSOP, SOIC, TSSOP)
S
I
A
0
I
A
1
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
S
E
Y
A
-Y
D
GND
V
CC
NC
V
CC
E
I
D
0
I
D
1
Y
A
I
B
0
I
B
1
Y
D
I
C
0
I
C
1
Y
B
GND
Y
C
Note 1: UQFN16 package die supply ground is connected to both GND pin and
exposed center pad. GND pin must be connected to supply ground for proper de-
vice operation. For enhanced thermal, electrical, and board level performance, the
exposed pad needs to be soldered to the board using a corresponding thermal pad
on the board and for proper heat conduction through the board, thermal vias need
to be incorporated in the PCB in the thermal pad region.
PI3B3257
Document Number DS40430 Rev 2-2
1
www.diodes.com
April 2018
Diodes Incorporated
A product Line of
Diodes Incorporated
PI3B3257
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 mplied. 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
0.8
±1
±1
±1
–1.2
5
8
8
17
V
Ω
µA
Typ.
(2)
Max.
Units
V
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
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)
Description
C
IN
Input Capacitance
C
OFFYN
C
OFFIN
C
ON
Y
N
Capacitance, Switch OFF
I
N
Capacitance, Switch OFF
I
N
/Y
N
Capacitance, Switch ON
Test Conditions
V
IN
= 0V
Typ.
3.0
17.0
8.5
25
Units
pF
Notes:
1. This parameter is determined by device characterization but is not production tested.
Power Supply Characteristics
Parameters
I
CC
∆I
CC
Description
Quiescent Power Supply Current
Supply Current per Input @ TTL
HIGH
(3, 4)
Test Conditions
(1)
V
CC
= Max.
V
CC
= Max.
V
IN
= GND or V
CC
V
IN
= 3.0
Min.
Typ.
(2)
0.1
Max.
3.0
750
Units
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.
PI3B3257
Document Number DS40430 Rev 2-2
2
www.diodes.com
April 2018
Diodes Incorporated
A product Line of
Diodes Incorporated
PI3B3257
Switching Characteristics Over Operating Range
PI3B3257
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
Min.
Com.
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 propaga-
tional 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.
