My Inquiry
My Account
Texas Instruments SN74LVC138APWR
- Part No.:
- SN74LVC138APWR
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 16-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
SN74LVC138APWR.pdf
- Description:
- IC DECODER/DEMUX 1X3:8 16TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:7,747
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74LVC138APWR from Texas Instruments is a 3-line to 8-line decoder/demultiplexer IC operating from 1.65 V to 3.6 V, featuring active-low dual enables (G2A, G2B), active-high enable (G1), and eight active-low outputs (Y0–Y7). It delivers 5.8 ns max propagation delay at 3.3 V and supports 5.5 V-tolerant inputs for mixed-voltage system interfacing. It is used in LED matrix column selection and memory address decoding.
For engineers reviewing the SN74LVC138APWR datasheet, SN74LVC138APWR pinout, SN74LVC138APWR application, or SN74LVC138APWR equivalent, key selection criteria include its 16-pin TSSOP package, 3.3-V logic compatibility, low propagation delay, 5.5-V input tolerance, and enable-input flexibility for cascaded decoding.
Technical Context
The SN74LVC138APWR implements a binary-select decoder with three address inputs (A, B, C) and three enable inputs (G1 high-active, G2A/G2B low-active) to activate exactly one of eight open-drain–compatible, active-low outputs. All outputs remain high when any enable is inactive - enabling hierarchical decoding without external inverters.
Its CMOS design ensures balanced drive strength (±24 mA at 3 V), low dynamic power (27 pF typical Cpd at 3.3 V), and robust ESD protection (2000 V HBM). Input voltage thresholds scale with VCC, supporting reliable operation across 1.65–3.6 V supply range while accepting 0–5.5 V input signals.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 1.65 V to 3.6 V - Enables direct integration into 1.8-V and 3.3-V systems without level shifters. |
| Input Voltage Tolerance | 0 V to 5.5 V - Allows safe interfacing with legacy 5-V controllers or mixed-voltage buses. |
| Max Propagation Delay | 5.8 ns at VCC = 3.3 V - Supports high-speed address decoding in sub-100-MHz digital systems. |
| Output Drive Strength | ±24 mA at VCC = 3 V - Sufficient to directly sink LED columns or drive light capacitive loads. |
| Power Dissipation Capacitance | 27 pF at VCC = 3.3 V - Predictable dynamic power consumption for timing and thermal analysis. |
| ESD Rating (HBM) | 2000 V - Meets industrial handling requirements without special ESD precautions beyond standard practice. |
Pinout & Package
TSSOP-16 (PW) package: 5.00 mm × 4.40 mm body, 0.65 mm pitch, surface-mount, moisture-sensitive level 1 (260°C reflow unlimited).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (G2A) | Active-low enable A | Must be LOW to enable decoding; used for hierarchical expansion with other decoders. |
| 2 (G2B) | Active-low enable B | Second low-enable input; both G2A and G2B must be LOW alongside G1 HIGH for output activation. |
| 3 (G1) | Active-high enable | Primary enable control; HIGH activates function only when G2A/G2B are also LOW. |
| 4 (C) | Most significant select input | MSB of 3-bit address bus; determines higher-order output group (Y4–Y7 vs Y0–Y3). |
| 5 (B) | Mid-significance select input | Center bit of address; combined with A/C, selects exact output line (Y0–Y7). |
| 6 (A) | Least significant select input | LSB of address; toggling A alone alternates between adjacent outputs (e.g., Y0↔Y1). |
| 7 (Y7) | Active-low output 7 | Asserted LOW when A=1, B=1, C=1 and all enables active; otherwise HIGH. |
| 8 (GND) | Ground reference | Return path for all internal logic and output current; requires low-impedance PCB connection. |
| 9 (Y6) | Active-low output 6 | Asserted LOW for A=0, B=1, C=1; complements Y7 in MSB decode group. |
| 10 (Y5) | Active-low output 5 | Asserted LOW for A=1, B=0, C=1; used in 3-to-8 mapping for peripheral address decoding. |
| 11 (Y4) | Active-low output 4 | Asserted LOW for A=0, B=0, C=1; enables selection of upper half of output bank. |
| 12 (Y3) | Active-low output 3 | Asserted LOW for A=1, B=1, C=0; commonly used for I/O port enable in microcontroller systems. |
| 13 (Y2) | Active-low output 2 | Asserted LOW for A=0, B=1, C=0; supports discrete peripheral selection in embedded control. |
| 14 (Y1) | Active-low output 1 | Asserted LOW for A=1, B=0, C=0; provides dedicated enable for secondary subsystems. |
| 15 (Y0) | Active-low output 0 | Asserted LOW for A=0, B=0, C=0; default output for reset or initialization signal routing. |
| 16 (VCC) | Positive supply | Core logic and output driver supply; requires local 0.1-µF bypass capacitor per TI layout guidelines. |
Key Features
| Feature | Design Value |
|---|---|
| 3-to-8 decoding with three enable inputs | Enables scalable address decoding up to 32 lines using only one external inverter - reduces gate count and board area. |
| 5.5-V tolerant inputs on 1.65–3.6-V supply | Eliminates need for external level translators when interfacing with 5-V microcontrollers or FPGAs. |
| 5.8 ns max tpd at 3.3 V | Minimizes added latency in memory access paths - critical for meeting tight timing budgets in high-speed systems. |
| ±24 mA output drive at 3 V | Directly drives LEDs, small relays, or logic inputs without buffer stages - simplifies BOM and layout. |
| 2000-V HBM ESD rating | Supports automated assembly and field service without specialized ESD handling - lowers manufacturing cost. |
Applications
| LED Matrix Column Driver | Memory Address Decoder |
|---|---|
|
Use Scenario: Driving 8-column common-anode LED matrix in embedded display subsystems. IC Role / Device Role / Timing Role: Low-side column selector that asserts one active-low output per scan cycle to illuminate single column. Use Value: Ensures only one column is enabled at a time, preventing current stacking and enabling uniform brightness via multiplexing. |
Use Scenario: Translating 3-bit microcontroller address lines into 8 discrete peripheral chip-select signals. IC Role / Device Role / Timing Role: Address-space partitioner that maps A/B/C inputs to individual device enables (e.g., UART, ADC, SPI flash). Use Value: Reduces GPIO usage and eliminates software-based bit-banging, improving deterministic response and code efficiency. |
| Industrial I/O Expansion | Programmable Logic Interface |
|
Use Scenario: Expanding PLC or motion controller digital outputs to drive solenoids, indicators, or sensors. IC Role / Device Role / Timing Role: Enable-gated demultiplexer where G1 accepts data stream and A/B/C select destination channel. Use Value: Allows single data line to route control bits to 8 independent loads - cuts wiring complexity and connector count. |
Use Scenario: Configuring FPGA or CPLD I/O banks by decoding configuration register bits. IC Role / Device Role / Timing Role: Static logic translator converting register-encoded mode settings into physical pin enables. Use Value: Provides glitch-free, combinatorial enable signals synchronized to clock domain - avoids metastability in config logic. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 3-to-8 decoder applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74HC138N | Higher VCC range (2–6 V), slower speed (25 ns @ 4.5 V), no 5.5-V input tolerance. | Requires level shifting in 3.3-V systems with 5-V inputs; unsuitable for mixed-voltage signal routing. | Choose for legacy 5-V-only designs where speed is non-critical and cost is prioritized. |
| 74LVT138PW | 3.3-V only supply (3–3.6 V), 3.5 ns tpd, TTL-compatible inputs, higher drive (±32 mA). | Not 5.5-V tolerant; incompatible with 1.8-V logic; requires strict 3.3-V rail regulation. | Choose when maximum speed and drive strength are required in pure 3.3-V environments with clean supplies. |
Compared with SN74HC138N and 74LVT138PW, the SN74LVC138APWR uniquely balances wide supply range (1.65–3.6 V), 5.5-V input tolerance, and sub-6-ns delay - making it optimal for modern mixed-signal embedded systems requiring interoperability and timing margin.
Availability
SN74LVC138APWR is available at Aetrix Electronics and suitable for LED displays, industrial I/O modules, and memory-mapped peripheral interfaces requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.
Supply support for SN74LVC138APWR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies with over 90 years of innovation in industrial, automotive, and communications markets.
The SN74LVC138APWR belongs to TI's LVC logic family, engineered for low-voltage, high-speed, mixed-signal interface applications - emphasizing voltage flexibility, noise immunity, and seamless integration into heterogeneous digital systems.
FAQ
What is the recommended operating voltage range for the SN74LVC138APWR?
The SN74LVC138APWR operates reliably from 1.65 V to 3.6 V. This range allows direct use in both 1.8-V and 3.3-V systems without voltage translation. Operation below 1.65 V may cause functional failure, and exceeding 3.6 V risks permanent damage. Always verify VCC stability within this window during power-up and transient conditions for the SN74LVC138APWR.
Can the SN74LVC138APWR accept 5-V input signals safely?
Yes, the SN74LVC138APWR features 5.5-V tolerant inputs - all control and select pins (A, B, C, G1, G2A, G2B) tolerate voltages up to 5.5 V regardless of VCC level. This allows direct connection to 5-V microcontrollers or FPGAs in mixed-voltage designs without external clamping or level-shifting circuitry for the SN74LVC138APWR.
How does the enable logic work on the SN74LVC138APWR?
The SN74LVC138APWR requires G1 HIGH and both G2A and G2B LOW to activate decoding. If any enable is violated, all outputs (Y0–Y7) go HIGH. This three-input enable scheme supports cascading - for example, connecting G1 of a second SN74LVC138APWR to Y0 of the first enables 24-line decoding without inverters.
What is the maximum output drive capability of the SN74LVC138APWR?
The SN74LVC138APWR delivers ±24 mA per output at VCC = 3 V, sufficient to sink typical LED column currents or drive logic inputs directly. At lower VCC (e.g., 1.8 V), drive drops to ±4 mA. Exceeding rated current risks output voltage degradation or thermal stress - always verify load conditions against the SN74LVC138APWR electrical characteristics table.
Is the SN74LVC138APWR pin-compatible with other 16-pin decoder ICs?
The SN74LVC138APWR in TSSOP-16 (PW) package shares identical pinout with SN74HC138, SN74LS138, and 74LVT138 - including VCC (pin 16), GND (pin 8), and output ordering (Y0–Y7 on pins 15–7). However, electrical behavior differs: SN74LVC138APWR offers wider VCC range and 5.5-V input tolerance not found in older families.
SN74LVC138APWR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74LVC
- Package/Case:
- 16-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Decoder/Demultiplexer
- Circuit:
- 1 x 3:8
- Independent Circuits:
- 1
- Current - Output High, Low:
- 24mA, 24mA
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 1.65V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-TSSOP
SN74LVC138APWR FAQ
1.How can I place an order for SN74LVC138APWR through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74LVC138APWR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SN74LVC138APWR reliable?
The price and inventory of SN74LVC138APWR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74LVC138APWR is usually 5 days.
3.What payment methods are accepted for SN74LVC138APWR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74LVC138APWR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74LVC138APWR?
SN74LVC138APWR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74LVC138APWR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SN74LVC138APWR?
For technical support, including SN74LVC138APWR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74LVC138APWR requirements.
6.How does Aetrix verify that SN74LVC138APWR is sourced from the original manufacturer or authorized distributors?
All SN74LVC138APWR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SN74LVC138APWR meets industry standards.
7.What is the process for return or replacement of SN74LVC138APWR?
All SN74LVC138APWR units undergo pre-shipment inspection (PSI). If there is an issue with SN74LVC138APWR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SN74LVC138APWR part is unused and in its original packaging.
Return procedure for SN74LVC138APWR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74LVC138APWR Tags
-
SN74HC138DR
Texas Instruments
-
TC7SB3157CFU,LF(CT
Toshiba Semiconductor and Storage
-
74CBTLV3257PW,118
Nexperia USA Inc.
-
SN74CBTLV3257PWR
Texas Instruments
-
74CBTLV3257GUX
Nexperia USA Inc.
-
74HC154BQ,118
Nexperia USA Inc.
-
P3S0200GMX
NXP USA Inc.
-
SN74CB3Q3245PWR
Texas Instruments
-
SN74CB3Q3257RGYR
Texas Instruments
-
TCA9543APWR
Texas Instruments
-
TCA9546APWR
Texas Instruments
-
SN74HC138N
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
