SN74ALS21ADR

Overview

The SN74ALS21ADR is a dual four-input positive AND gate manufactured by Texas Instruments. It belongs to the ALS logic series and operates within a supply voltage range of 4.5 V to 5.5 V. The device features two independent gates, each with four inputs and one output, housed in a 14-SOIC surface-mount package. Key electrical specifications include a low-level output current of 8 mA and a high-level output current of -400 µA. The propagation delay is specified at 15 ns under standard conditions. It supports a commercial operating temperature range from 0°C to +70°C.

Feature Summary

• Dual four-input positive AND logic functionality
• High-speed ALS technology for reduced power consumption
• Push-pull output structure for improved drive capability

Applications

• Digital logic circuits requiring multi-input AND operations
• Data processing systems utilizing TTL-compatible interfaces
• Control logic in industrial automation equipment

Procurement Notes

Verify the specific ordering suffix 'R' indicates tape-and-reel packaging when sourcing components. Confirm RoHS compliance status through official manufacturer documentation or certified distributor declarations. Ensure the procurement channel provides valid traceability for the Texas Instruments manufacturing origin. Cross-reference the full part number against current datasheets to validate pinout and electrical characteristics before integration into design projects.

Selection Notes

Select this component for applications requiring moderate speed and low power dissipation typical of the ALS family. It serves as a direct replacement for older 74S21 variants where lower power is prioritized over maximum speed. Consider the SOIC-14 package constraints for PCB layout and thermal management. Evaluate the 4.5 V to 5.5 V supply requirement against system power rails to ensure compatibility without additional level shifting.

Part Context

This device is part of the broader SN74ALS21A family of logic gates produced by Texas Instruments. It shares functional similarities with other ALS-series components but is distinct in its specific dual four-input AND configuration. The 'ADR' designation identifies the specific reel-packaged variant of the SOIC-14 housing. It complements other logic families like HC or HCT but offers different performance trade-offs regarding speed and power.

Replacement Considerations

SN74ALS21ADRG4 is a verified equivalent part number representing the same functional device with potential manufacturing process updates.