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www.diodes.com

April 2018

Diodes Incorporated

PI3B3257

Document Number DS40430 Rev 2-2

Pin Description

Pin Name

Description

Data Inputs

S

Select Inputs

E

Enable

Data Outputs

GND

Power

NC

No Connect

Description

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.

Block Diagram

Features

¼

Near-Zero propagation delay

¼

5Ω switches connect inputs to outputs

¼

Fast Switching Speed: 4.8ns max.

¼

Ultra-Low Quiescent Power: 0.1µA typical

– Ideally suited for notebook applications

¼

Pin compatible with 74 series 257 logic devices

¼

Packaging (Pb-free & Green avaliable):

– 16-pin, QSOP (Q)

– 16-pin, SOIC (W)

– 16-pin, TSSOP (L)

– 16-pin, UQFN (ZHD)

Pin Configuration

(QSOP, SOIC, TSSOP)

Note:

1. H = High Voltage Level

L = Low Voltage Level

E

S

IY

E

SW

SW

SW

SW

SW

SW

SW

SW

SW

E

S

Function

H

X

Hi-Z Hi-Z

Hi-Z

Hi-Z

Disable

L

L

S = 0

L

H

S = 1

S

1

E

2

I

3

4

I

5

16

I

6

15

7

14

8

13

12

GND

11

10

9

A product Line of

Diodes Incorporated

PI3B3257

1

2

3

4

5

6

7

8

12

11

10

9

16

15

14

13

S

I 0

A

I 1

A

A

Y

C

Y

I 1

C

I 0

C

D

Y

Pin Configuration

(UQFN)

3.3V, Quad 2:1 Mux/DeMux NanoSwitch™

Transparent top view

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.