SN74ALS280D

Overview

The SN74ALS280D is a universal 9-bit parity generator and checker utilizing advanced Schottky high-performance circuitry. It provides complementary odd (Σ ODD) and even (Σ EVEN) outputs to support both parity schemes. The device operates within a supply voltage range of 4.5 V to 5.5 V and features an operating temperature range from 0°C to 70°C. Propagation delays for the ALS variant reach up to 22 ns under standard load conditions.

Feature Summary

• Generates or checks parity for nine data lines with dedicated odd and even outputs
• Cascadable architecture allows expansion for n-bit parity applications
• Compatible with existing MSI parity circuits without expander inputs

Applications

• System upgrades replacing SN74ALS180 and SN74AS180 parity generators/checkers
• Implementation of 25-line parity generator/checker circuits
• Construction of 81-line parity generator/checker systems via cascading

Procurement Notes

Verify the specific package configuration, as the 'D' suffix indicates a plastic small-outline package. Confirm that the required logic family matches the ALS series specifications rather than the AS series. Ensure the application environment remains within the specified 0°C to 70°C operating temperature range during deployment.

Selection Notes

Select this component when upgrading legacy designs requiring 9-bit parity generation or checking. The absence of internal connections at terminal 3 and the availability of input I at terminal 4 facilitate direct substitution for older MSI parity circuits. Verify compatibility with existing system voltage levels and timing requirements before integration.

Part Context

This device belongs to the Texas Instruments SN74ALS logic family, characterized by advanced Schottky technology for high-speed performance. It serves as a functional equivalent to the SN74AS280 but with distinct electrical characteristics tailored for low-power, high-speed digital applications within the standard 74-series ecosystem.

Replacement Considerations

The SN74ALS280D can substitute for SN74ALS180 and SN74AS180 devices in existing designs to produce identical functions. It may also be mixed with these older devices in the same system without functional degradation.