My Inquiry
My Account
Texas Instruments SN74LS157DE4
- Part No.:
- SN74LS157DE4
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SN74LS157DE4.pdf
- Description:
- IC MULTIPLEXER 4 X 2:1 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,059
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74LS157DE4 from Texas Instruments is a quad 2-line-to-1-line data selector/multiplexer in a 16-pin SOIC package, operating from 0°C to 70°C with typical propagation delay of 15 ns and supply current of 19 mA at 5 V. It performs logic-level signal routing in digital control systems, bus management, and address/data path selection.
For engineers reviewing the SN74LS157DE4 datasheet, SN74LS157DE4 pinout, SN74LS157DE4 application, or SN74LS157DE4 equivalent, key selection criteria include its TTL-compatible input thresholds, complementary output enable control, guaranteed fan-out of 20 LS-TTL loads, and compatibility with legacy 74LS logic families in industrial control and test equipment design.
Technical Context
The SN74LS157DE4 implements four independent 2:1 multiplexers sharing a common strobe (enable) input and common select line. Each channel routes either input A or B to its Y output based on the select state, with active-low enable asserting outputs only when low.
All inputs are TTL-compatible with VIH = 2.0 V min and VIL = 0.8 V max; outputs drive standard LS-TTL loads with VOH = 2.7 V min at IOL = 8 mA and VOL = 0.5 V max at IOH = 400 µA. No internal latching or clocking is present - operation is purely combinational.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | 74LS TTL - ensures interoperability with legacy LS-based systems and predictable noise margins. |
| Propagation Delay | 15 ns typical at VCC = 5 V - supports reliable operation up to ~30 MHz in non-critical timing paths. |
| Supply Voltage | 4.75 V to 5.25 V - requires regulated 5 V rail; not tolerant of wider voltage ranges. |
| Fan-Out | 20 LS-TTL loads - enables direct driving of multiple downstream gates without buffering. |
| Operating Temperature | 0°C to 70°C - rated for commercial-grade environments, not extended or military temperature ranges. |
| Package | SOIC (D) with 16 pins - surface-mount footprint compatible with automated assembly and IPC-7351 NS0016A land pattern. |
Pinout & Package
SN74LS157DE4 is housed in a 16-pin Small Outline Integrated Circuit (SOIC) package, 3.9 mm wide, with 1.27 mm pitch and 2.00 mm max height per TI NS0016A drawing. Pin 1 is located at the top-left corner with notch or beveled edge marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1G | Active-low enable input | When high, all Y outputs are forced high-impedance; enables multiplexing only when low. |
| 1A–4A | Data inputs A | First set of four data inputs, routed to corresponding Y outputs when S = low. |
| 1B–4B | Data inputs B | Second set of four data inputs, routed to corresponding Y outputs when S = high. |
| S | Select control | Single line determining source: A (S = L) or B (S = H) for all four channels simultaneously. |
| 1Y–4Y | Outputs | Complementary to inputs - no inversion; each Y reflects selected A or B input state. |
| VCC, GND | Power terminals | Pins 16 and 8 respectively - decoupling capacitor placement near these pins is critical for noise immunity. |
Key Features
| Feature | Design Value |
|---|---|
| Quad 2:1 multiplexer function | Four independent channels share one select and one enable - reduces component count in parallel data routing. |
| Complementary output structure | Outputs replicate input logic states without inversion - eliminates need for external inverters in most routing applications. |
| TTL-compatible interface levels | VIH = 2.0 V min / VIL = 0.8 V max ensures robust interfacing with standard 74LS/74F logic without level-shifting. |
| High fan-out capability | Drives 20 LS-TTL loads directly - supports daisy-chained control signals in backplane or motherboard designs. |
Applications
| Bus Arbitration Logic | Microprocessor Address Decoding |
|---|---|
Use Scenario: Selecting between two peripheral data buses connected to a single CPU data bus. IC Role / Device Role / Timing Role: Data path selector enabling time-shared access to dual memory or I/O modules. Use Value: Eliminates need for discrete AND/OR gating; maintains signal integrity with 15 ns delay and LS-TTL drive strength. | Use Scenario: Routing upper address bits from CPU to multiple memory banks based on chip-select logic. IC Role / Device Role / Timing Role: Address multiplexer resolving bank selection during instruction fetch or data read cycles. Use Value: Ensures deterministic timing with guaranteed 15 ns max propagation and no metastability risk due to combinational-only operation. |
| Digital Test Equipment Signal Routing | Legacy Industrial Control Panel Interface |
Use Scenario: Switching calibration reference signals into ADC input paths during self-test sequences. IC Role / Device Role / Timing Role: Precision analog-digital interface multiplexer controlled by microcontroller GPIO. Use Value: TTL-compatible inputs simplify MCU interface; 0.5 V max VOL ensures clean low-state detection in mixed-signal test fixtures. | Use Scenario: Consolidating operator panel switch inputs (mode, reset, jog) onto shared controller input lines. IC Role / Device Role / Timing Role: Input signal combiner reducing I/O pin count on aging PLC or motion controller. Use Value: Direct compatibility with existing 5 V TTL panel wiring avoids redesign; 20-load fan-out supports parallel LED status feedback. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad 2:1 multiplexer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LS157N | Same logic function and electrical specs, but in 16-pin PDIP package with through-hole mounting. | Suitable for prototyping, manual assembly, or legacy board rework where SOIC footprint is unavailable. | Choose SN74LS157N for breadboarding or repair of through-hole systems; SN74LS157DE4 is preferred for volume SMT production. |
| SN74LS257N | Identical functionality and pinout, but with three-state outputs enabled by separate 1G and 2G controls instead of single 1G. | Required when individual channel tri-state control is needed, e.g., for bidirectional bus arbitration or shared data lines. | Use SN74LS257N only if independent output disable per channel is required; SN74LS157DE4 suffices for simple A/B selection with global enable. |
Compared with SN74LS157N, SN74LS157DE4 offers identical logic behavior in a space-saving SOIC package ideal for modern PCB layouts, while SN74LS257N adds tri-state flexibility at the cost of increased control complexity - neither is pin-compatible with SN74LS157DE4 due to differing enable architecture and output behavior.
Availability
SN74LS157DE4 is available at Aetrix Electronics and suitable for industrial control panels, legacy test equipment upgrades, and microprocessor bus expansion requiring stable component supply across long-lifecycle programs.
Supply support for SN74LS157DE4 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 U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.
The SN74LS157DE4 belongs to TI's legacy 74LS logic family, designed specifically for backward compatibility with first-generation TTL systems while delivering improved speed-power trade-offs over original 74-series devices.
FAQ
What is the maximum clock frequency supported by SN74LS157DE4?
The SN74LS157DE4 is a combinational logic device with no internal clock - it does not operate at a "clock frequency." Its usable data rate depends on propagation delay (15 ns typical) and system timing margins. In practice, SN74LS157DE4 reliably supports data switching up to approximately 30 MHz in well-designed PCB layouts with proper decoupling and termination.
Does SN74LS157DE4 support 3.3 V logic interfaces?
No, SN74LS157DE4 is strictly a 5 V TTL device. Its input thresholds (VIH = 2.0 V min, VIL = 0.8 V max) and output drive characteristics are specified only for VCC = 4.75–5.25 V. Interfacing SN74LS157DE4 directly with 3.3 V logic requires level-shifting circuitry to avoid undefined operation or excessive input current.
Can SN74LS157DE4 outputs drive LEDs directly?
Yes, SN74LS157DE4 outputs can sink up to 8 mA (VOL = 0.5 V max at IOL = 8 mA), sufficient to drive standard indicator LEDs with appropriate current-limiting resistors (e.g., 330 Ω for ~10 mA at 5 V). However, it cannot source significant current (IOH = 400 µA max), so LEDs must be connected anode-to-VCC and cathode-to-Y output for active-low indication.
Is SN74LS157DE4 RoHS compliant?
Yes, SN74LS157DE4 is RoHS compliant, with lead finish NIPDAU (nickel/palladium/gold) and MSL Level-1 rating per JEDEC J-STD-020. It meets EU Directive 2011/65/EU requirements and carries no exemption codes - verified via TI's official packaging documentation dated 15-Jul-2026.
How does SN74LS157DE4 differ from SN74LS158?
SN74LS157DE4 is a quad 2:1 multiplexer with complementary (non-inverting) outputs, while SN74LS158 is functionally identical but provides inverted outputs. Both share the same pinout, timing, and electrical specs - the sole functional difference is output polarity. SN74LS157DE4 is selected when signal inversion is undesirable or handled elsewhere in the system.
SN74LS157DE4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74LS
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Type:
- Multiplexer
- Circuit:
- 4 x 2:1
- Independent Circuits:
- 1
- Current - Output High, Low:
- 400µA, 8mA
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 4.75V ~ 5.25V
- Operating Temperature:
- 0°C ~ 70°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
SN74LS157DE4 FAQ
1.How can I place an order for SN74LS157DE4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74LS157DE4 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 SN74LS157DE4 reliable?
The price and inventory of SN74LS157DE4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74LS157DE4 is usually 5 days.
3.What payment methods are accepted for SN74LS157DE4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74LS157DE4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74LS157DE4?
SN74LS157DE4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74LS157DE4 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 SN74LS157DE4?
For technical support, including SN74LS157DE4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74LS157DE4 requirements.
6.How does Aetrix verify that SN74LS157DE4 is sourced from the original manufacturer or authorized distributors?
All SN74LS157DE4 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 SN74LS157DE4 meets industry standards.
7.What is the process for return or replacement of SN74LS157DE4?
All SN74LS157DE4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74LS157DE4, 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 SN74LS157DE4 part is unused and in its original packaging.
Return procedure for SN74LS157DE4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74LS157DE4 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…
