SN74LS21DIn StockTexas Instruments
SN74LS21D is a dual 4-input positive-AND gate IC from Texas Instruments, featuring TTL-compatible LS-family logic with totem-pole outputs and 15 pF load capacitance. Ideal for digital logic design, signal gating, and embedded control systems. From $0.196, in stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 14
- Lifecycle
- OBSOLETE
- Datasheet
- SN74LS21D Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.1960(MOQ 1)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Dual independent 4-input AND gate in a single 14-pin SOIC package
- LS-family TTL logic with totem-pole outputs for reliable drive capability
- Low load capacitance of 15 pF enabling high-speed switching performance
- Max output low current (I(ol)) of 8 mA supporting standard TTL fan-out
- JEDEC JESD-609 e4 compliant, RoHS-friendly for modern design requirements
Applications
The SN74LS21D is widely used in digital logic design for combining multiple control signals in microprocessor bus arbitration, address decoding, and enable logic. Its dual 4-input AND configuration makes it suitable for programmable logic replacement, FPGA glue logic, and industrial control circuits. The LS TTL family compatibility ensures seamless integration into legacy and new embedded systems requiring reliable combinational logic gating.
Specifications
| YTEOL | 0 |
| Family | LS |
| JESD-30 Code | R-PDSO-G14 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 15pF |
| Logic IC Type | AND GATE |
| Max I(ol) | 0.008A |
| Number of Functions | 2 |
| Number of Inputs | 4 |
| Output Characteristics | TOTEM-POLE |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP14,.25 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Packing Method | TUBE |
| Peak Reflow Temperature (Cel) | 260 |
| Power Supply Current-Max (ICC) | 4.4mA |
| Prop. Delay@Nom-Sup | 20ns |
| Propagation Delay (tpd) | 20ns |
| Qualification Status | Not Qualified |
| Schmitt Trigger | NO |
| Supply Voltage-Max (Vsup) | 5.25V |
| Supply Voltage-Min (Vsup) | 4.75V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | YES |
| Technology | TTL |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.01 |
| Country of Origin | Malaysia |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What is the SN74LS21D and what logic function does it perform?
The SN74LS21D is a dual 4-input positive-AND gate IC from Texas Instruments. It contains two independent AND gates, each with 4 inputs, and produces a HIGH output only when all four inputs are HIGH. It operates in the LS (Low-power Schottky) TTL logic family with totem-pole outputs and a load capacitance of 15 pF.
What are the key electrical specifications of the SN74LS21D?
The SN74LS21D features a maximum output low current (I(ol)) of 8 mA, a load capacitance (CL) of 15 pF, and totem-pole output configuration. It belongs to the LS TTL logic family and is housed in a 14-pin Small Outline (SOIC) package (JESD-30 code R-PDSO-G14), suitable for surface-mount assembly.
What are typical applications for the SN74LS21D?
The SN74LS21D is commonly used in address decoding, bus arbitration, enable logic, and digital signal gating in embedded and industrial systems. Its dual 4-input AND gate structure is ideal for combining multiple control signals in microprocessor systems, FPGA glue logic, and legacy TTL-compatible designs.
What package does the SN74LS21D come in, and are there alternative package options?
The SN74LS21D is available in a 14-pin Small Outline Integrated Circuit (SOIC) package, suitable for surface-mount PCB assembly. Texas Instruments also offers the SN74LS21N in a 14-pin DIP (through-hole) package for breadboard prototyping and through-hole applications.
Where can I buy the SN74LS21D and what is the price?
The SN74LS21D is available from major electronic component distributors worldwide, including Digi-Key, Mouser, and Arrow. Pricing starts from approximately $0.196 per unit at volume quantities. FindMyChip provides real-time stock and pricing comparisons to help you source the best deal with worldwide shipping options.
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Why Buy from FindMyChip
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 |
|---|---|---|
| 1+ | $0.4200 | $0.42 |
| 13+ | $0.3500 | $4.55 |
| 58+ | $0.2800 | $16.24 |
| 215+ | $0.1960 | $42.14 |
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