SN74AS280DR

Overview

The SN74AS280DR is a universal 9-bit parity generator/checker utilizing advanced Schottky high-performance circuitry. It provides complementary Σ EVEN and Σ ODD outputs to support both odd- and even-parity applications. The device operates within a supply voltage range of 4.5 V to 5.5 V and features buffered inputs to reduce drive requirements. Propagation delays are specified between 3 ns and 12 ns depending on the output state, with low-level output current capability of 20 mA.

Feature Summary

• Generates or checks parity for nine data lines using advanced Schottky circuitry
• Provides distinct outputs for odd and even parity configurations
• Inputs are buffered to lower system drive requirements
• Supports cascading for expanded word-length parity generation

Applications

• System upgrades replacing existing MSI parity circuits
• Cascaded implementations for up to 81-bit parity generation
• Data integrity verification in digital communication systems

Procurement Notes

Verify that the specific ordering suffix corresponds to the SOIC package type required for your design. Confirm the moisture sensitivity level and reflow temperature profile align with your assembly process capabilities. Ensure the operating temperature range meets your environmental specifications before finalizing procurement.

Selection Notes

Select this component when upgrading legacy designs involving SN74ALS180 or SN74AS180 devices. The absence of internal connections at terminal 3 allows it to function identically to expander-equipped predecessors. Verify that the 20 mA low-level output current meets the load requirements of your downstream logic gates.

Part Context

This device belongs to the Texas Instruments SN74AS series, which utilizes advanced Schottky technology for high-speed performance. It serves as a direct functional replacement for older parity generator/checkers while offering improved switching characteristics. The DR suffix indicates the plastic small-outline package variant suitable for surface-mount applications.

Replacement Considerations

SN74ALS280DR

FAQ

How does the SN74AS280 handle expansion beyond 9 bits?

The device supports cascading to implement parity generation for word lengths up to 81 bits by connecting multiple units.

What is the significance of terminal 3 on the SN74AS280?

Terminal 3 has no internal connection, allowing the device to substitute for parts like the SN74ALS180 that utilize this pin for expander functions.