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SN74LVC138A-Q1 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER
SCAS708B – SEPTEMBER 2003 – REVISED FEBRUARY 2008
FEATURES
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• Qualified for Automotive Applications • ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V Using Machine Model (C = 200 pF, R = 0)
• Operates From 2 V to 3.6 V • Inputs Accept Voltages to 5.5 V • Max tpd of 5.8 ns at 3.3 V • Typical VOLP (Output Ground Bounce) < 0.8 V
at VCC = 3.3 V, TA = 25°C • Typical VOHV (Output VOH Undershoot) > 2 V
at VCC = 3.3 V, TA = 25°C
D OR PW PACKAGE (TOP VIEW)
A B C G2A G2B G1 Y7 GND
1 2 3 4 5 6 7 8
16 VCC 15 Y0 14 Y1 13 Y2 12 Y3 11 Y4 10 Y5 9 Y6
DESCRIPTION/ORDERING INFORMATION
The SN74LVC138A 3-line to 8-line decoder/demultiplexer is designed for 2.7-V to 3.6-V VCC operation.
The device is designed for high-performance memory-decoding or data-routing applications requiring very short propagation delay times. In high-performance memory systems, this decoder minimizes the effects of system decoding. When employed with high-speed memories utilizing a fast enable circuit, 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 enable inputs and one active-high enable input 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.
Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of this device as a translator in a mixed 3.3-V/5-V system environment.
TA –40°C to 125°C
SOIC – D TSSOP – PW
ORDERING INFORMATION(1)
PACKAGE (2)
ORDERABLE PART NUMBER
Reel of 2500
SN74LVC138AQDRQ1
Reel of 2000
SN74LVC138AQPWRQ1
TOP-SIDE MARKING L138AQ1 L138AQ1
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI web site at www.ti.com.
(2) Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.
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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.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Copyright © 2003–2008, Texas Instruments Incorporated
SN74LVC138A-Q1 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER
SCAS708B – SEPTEMBER 2003 – REVISED FEBRUARY 2008
www.ti.com
FUNCTION TABLE
ENABLE INPUTS SELECT INPUTS
OUTPUTS
G1 G2A G2B C B A Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
XHXXXXHHHHHHHH
XXHXXXHHHHHHHH
L XXXXXHHHHHHHH
HL L L L L LHHHHHHH
HL L L LHHL HHHHHH
HL L L HLHHLHHHHH
HL L L HHHHHLHHHH
HL LHL LHHHHL HHH
HL LHLHHHHHHLHH
HL LHHLHHHHHHLH
HL LHHHHHHHHHHL
LOGIC DIAGRAM (POSITIVE LOGIC)
1 A
Select Inputs
2 B
3 C
6 G1
Enable Inputs
4 G2A
5 G2B
15 Y0
14 Y1
13 Y2
12 Y3 11 Y4
Data Outputs
10 Y5
9 Y6
7 Y7
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Copyright © 2003–2008, Texas Instruments Incorporated
Product Folder Link(s): SN74LVC138A-Q1
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SN74LVC138A-Q1 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER
SCAS708B – SEPTEMBER 2003 – REVISED FEBRUARY 2008
Absolute Maximum Ratings(1)
over operating free-air temperature range (unless otherwise noted)
VCC Supply voltage range VI Input voltage range(2) VO Output voltage range(2)(3) IIK Input clamp current IOK Output clamp current IO Continuous output current
Continuous current through VCC or GND
θJA Package thermal impedance(4)
Tstg Storage temperature range
VI < 0 VO < 0
D package PW package
MIN –0.5 –0.5 –0.5
–65
MAX 6.5 6.5
VCC + 0.5 –50 –50 ±50
±100 73
108 150
UNIT V V V mA mA mA mA
°C/W
°C
(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) The input and output negative-voltage ratings may be exceeded if the input and output current ratings are observed. (3) The value of VCC is provided in the recommended operating conditions table. (4) The package thermal impedance is calculated in accordance with JESD 51-7.
Recommended Operating Conditions(1)
VCC Supply voltage
VIH High-level input voltage VIL Low-level input voltage VI Input volt.