SN74ALS251NIn StockTexas Instruments
SN74ALS251N is a 1-of-8 data selector/multiplexer IC with 3-state outputs from Texas Instruments. Features 8-input selection, 50 pF load capacitance, and 24 mA output current. Ideal for data routing and bus control applications. From $1.08 in stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Dual-In-Line Packages
- Pin Count
- 16
- Lifecycle
- ACTIVE
- Datasheet
- SN74ALS251N Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $1.0773(MOQ 173)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 1-of-8 data selection with 3-state outputs for bus-sharing applications
- High-speed ALS logic family with 50 pF load capacitance support
- 24 mA output sink current (I(ol)) for robust drive capability
- Standard DIP-16 package for easy through-hole PCB integration
- Single function multiplexer supporting 8 inputs with active-low strobe
Applications
The SN74ALS251N is widely used in data routing and bus multiplexing applications within digital logic systems. It is commonly found in microprocessor address and data bus management, memory bank selection, and programmable logic controller (PLC) I/O expansion circuits. Its 3-state outputs make it suitable for shared bus architectures in industrial and embedded control systems.
Specifications
| YTEOL | 15 |
| Family | ALS |
| JESD-30 Code | R-PDIP-T16 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 50pF |
| Logic IC Type | MULTIPLEXER |
| Max I(ol) | 0.024A |
| Number of Bits | 8 |
| Number of Functions | 1 |
| Number of Inputs | 8 |
| Number of Outputs | 1 |
| Output Characteristics | 3-STATE |
| Output Polarity | COMPLEMENTARY |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | DIP16,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Packing Method | TUBE |
| Power Supply Current-Max (ICC) | 10mA |
| Prop. Delay@Nom-Sup | 24ns |
| Propagation Delay (tpd) | 24ns |
| Qualification Status | Not Qualified |
| Supply Voltage-Max (Vsup) | 5.5V |
| Supply Voltage-Min (Vsup) | 4.5V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | NO |
| Technology | TTL |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
| Country of Origin | Malaysia, Mexico |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74ALS251N:
Multiplexer, ALS Series, 1-Func, 8 Line Input, 1 Line Output, Complementary Output, TTL, PDIP16
Multiplexer, ALS Series, 1-Func, 8 Line Input, 1 Line Output, Complementary Output, TTL, PDSO16
Multiplexer, ALS Series, 1-Func, 8 Line Input, 1 Line Output, Complementary Output, TTL, PDSO16
Frequently Asked Questions
What is the SN74ALS251N and what does it do?
The SN74ALS251N is a 1-of-8 data selector/multiplexer with 3-state outputs from Texas Instruments. It selects one of 8 input data lines based on a 3-bit binary address and routes it to a single output, supporting bus-sharing with its 3-state output capability. It operates in the ALS (Advanced Low-power Schottky) logic family.
What are the key electrical specifications of the SN74ALS251N?
The SN74ALS251N features a maximum output sink current (I(ol)) of 24 mA, a load capacitance (CL) of 50 pF, and is housed in a 16-pin Dual-In-Line (DIP) package. It belongs to the ALS logic family, offering fast switching speeds and low power consumption compared to standard TTL devices.
What are the typical applications for the SN74ALS251N?
Typical applications include microprocessor bus multiplexing, memory bank selection, data routing in industrial control systems, and I/O expansion in embedded systems. The 3-state outputs allow multiple devices to share a common data bus without signal contention, making it ideal for complex digital system designs.
What package type does the SN74ALS251N come in, and are there alternative packages?
The SN74ALS251N comes in a 16-pin Dual-In-Line (DIP) package, suitable for through-hole PCB mounting. Texas Instruments also offers the SN74ALS251D in an SOIC surface-mount package and the SN74ALS251NSR in a tape-and-reel format for automated assembly, providing flexibility for different board design requirements.
Is the SN74ALS251N still in production, and what are potential replacement options?
The SN74ALS251N is available from authorized distributors with a price starting around $1.08 per unit. Functional alternatives include the SN74LS251N (standard LS logic) and the SN74HC251 (CMOS, lower power). For a drop-in ALS replacement, the SN74ALS251D in SOIC package is also an option depending on your PCB layout.
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About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 173+ | $1.7400 | $301.02 |
| 1000+ | $1.1500 | $1150.00 |
| 2500+ | $1.1200 | $2800.00 |
| 5000+ | $1.0900 | $5450.00 |
| 100000+ | $1.0773 | $107730.00 |
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