Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLogic ICsLogic IC - Demultiplexer, decoder Decoder/demultiplexer Single supply SOIC 16 N

CD74AC238

3-LINE TO 8-LINE DECODER/DEMULTIPLEXER

SCHS331 – FEBRUARY 2003

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

AC Types Feature 1.5-V to 5.5-V Operation

and Balanced Noise Immunity at 30% of the

Supply Voltage

Speed of Bipolar F, AS, and S, With

Significantly Reduced Power Consumption

Designed Specifically for High-Speed

Memory Decoders and Data-Transmission

Systems

Incorporates Three Enable Inputs to

Simplify Cascading and/or Data Reception

Balanced Propagation Delays

±24-mA Output Drive Current

– Fanout to 15 F Devices

SCR-Latchup-Resistant CMOS Process and

Circuit Design

Exceeds 2-kV ESD Protection Per

MIL-STD-883, Method 3015

description/ordering information

The CD74AC238 decoder/demultiplexer is designed for high-performance memory-decoding and data-routing

applications that require very short propagation-delay times. In high-performance memory systems, this

decoder can be used to minimize the effects of system decoding. When employed with high-speed memories

utilizing a fast enable circuit, the delay times of this decoder and the enable time of the memory usually are less

than the typical access time of the memory. This means that the effective system delay introduced by the

decoder is negligible.

The conditions at the binary-select inputs and the three enable inputs select one of eight output lines. Two

active-low and one active-high enable inputs reduce the need for external gates or inverters when expanding.

A 24-line decoder can be implemented without external inverters, and a 32-line decoder requires only one

inverter. An enable input can be used as a data input for demultiplexing applications (see Application

Information).

ORDERING INFORMATION

PACKAGE

†

ORDERABLE

PART NUMBER

TOP-SIDE

MARKING

–55°C to 125°C SOIC – M Tape and reel CD74AC238M96 AC238M

†

Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines

are available at www.ti.com/sc/package.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

GND

M PACKAGE

(TOP VIEW)

Summary of content (14 pages)

PAGE 1
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 D D D D D D D D M PACKAGE (TOP VIEW) AC Types Feature 1.5-V to 5.
PAGE 2
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 FUNCTION TABLE SELECT INPUTS ENABLE INPUTS G1 G2A G2B C B X X H X X X X H X X A OUTPUTS Y0 Y1 Y2 Y3 Y4 X L X L Y5 Y6 L L L L L L L L L L L L L L L X X X X X L L L L L L L L H L L L L L H L L L L L L L H L L L L H L H L L L L L L H L L L H L L L H L L L L L H L L L H H L L L H L L L L H L L H L L L L L L H L L L
PAGE 3
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 absolute maximum ratings over operating free-air temperature range (unless otherwise noted)† Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 6 V Input clamp current, IIK (VI < 0 V or VI > VCC) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PAGE 4
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) PARAMETER TEST CONDITIONS VCC MIN IOH = –50 µA VOH VI = VIH or VIL IOH = –4 mA IOH = –24 mA IOH = –50 mA† IOH = –75 mA† IOL = 50 µA VOL II ICC VI = VIH or VIL VI = VCC or GND VI = VCC or GND, –55°C to 125°C TA = 25°C MAX MIN –40°C to 85°C MAX MIN 1.5 V 1.4 1.4 1.4 2.9 3V 2.9 2.9 4.5 V 4.4 4.4 4.4 3V 2.
PAGE 5
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 switching characteristics over recommended operating free-air temperature range, VCC = 3.3 V ± 0.3 V, CL = 50 pF (unless otherwise noted) (see Figure 1) FROM (INPUT) TO (OUTPUT) tPLH tPHL A B A, B, C Any Y tPLH tPHL G1 Any Y tPLH tPHL G2A G2B G2A, Any Y PARAMETER –55°C to 125°C –40°C to 85°C MIN MAX MIN MAX 5.3 21 5.4 19.1 5.3 21 5.4 19.1 5.8 23.2 6 21.1 5.8 23.2 6 21.1 4.2 16.7 4.3 15.2 4.2 16.
PAGE 6
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 PARAMETER MEASUREMENT INFORMATION S1 R1 = 500 Ω† From Output Under Test 2 × VCC Open GND CL = 50 pF (see Note A) R2 = 500 Ω† TEST S1 tPLH/tPHL tPLZ/tPZL tPHZ/tPZH Open 2 × VCC GND tw VCC † When VCC = 1.
PAGE 7
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 APPLICATION INFORMATION CD74AC238 BIN/OCT 1 2 3 VCC 0 1 1 2 2 4 6 3 & 4 4 EN 5 5 6 7 15 14 13 12 11 10 9 7 0 1 2 3 4 5 6 7 CD74AC238 BIN/OCT 1 A0 2 A1 3 A2 1 2 2 4 6 A3 0 1 3 & 4 4 A4 EN 5 5 6 7 15 14 13 12 11 10 9 7 8 9 10 11 12 13 14 15 CD74AC238 BIN/OCT 1 2 3 6 0 1 1 2 2 4 3 & 4 4 5 EN 5 6 7 15 14 13 12 11 10 9 7 16 17 18 19 20 21 22 23 Figure 2.
PAGE 8
CD74AC238 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER SCHS331 – FEBRUARY 2003 APPLICATION INFORMATION CD74AC238 BIN/OCT 1 A0 2 A1 3 A2 1 1 2 2 4 6 VCC 0 3 & 4 4 A3 EN 5 A4 5 6 7 15 14 13 12 11 10 9 7 0 1 2 3 4 5 6 7 CD74AC238 BIN/OCT 1 2 3 0 1 1 2 2 4 6 3 & 4 4 EN 5 5 6 7 15 14 13 12 11 10 9 7 8 9 10 11 12 13 14 15 CD74AC238 BIN/OCT 1 2 3 0 1 1 2 2 4 6 3 & 4 4 EN 5 5 6 7 15 14 13 12 11 10 9 7 16 17 18 19 20 21 22 23 CD74AC238 BIN/OCT 1 2 3 6 0 1 1 2 2 4 3
PAGE 9
PACKAGE OPTION ADDENDUM www.ti.
PAGE 10
PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device CD74AC238M96 Package Package Pins Type Drawing SOIC D 16 SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 2500 330.0 16.4 Pack Materials-Page 1 6.5 B0 (mm) K0 (mm) P1 (mm) 10.3 2.1 8.0 W Pin1 (mm) Quadrant 16.
PAGE 11
PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) CD74AC238M96 SOIC D 16 2500 333.2 345.9 28.
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