SN74LS145DR

Overview

The SN74LS145DR is a BCD-to-decimal decoder/driver from the Texas Instruments LS series. It features four binary inputs and ten active-low decoded outputs. The device operates on a single power supply ranging from 4.75 V to 5.25 V. Key electrical parameters include a propagation delay of 50 ns, a bandwidth of 35 MHz, and an接通延迟 time of 50 ns. Output capabilities specify a high-level output current of -250 μA and a low-level output current of 80 mA. The component draws 1 mA of supply current and functions within a temperature range of 0°C to 70°C.

Feature Summary

• Converts four-bit binary coded decimal inputs into one of ten active-low decoded outputs.
• Provides open-collector outputs suitable for driving external loads or interfacing with other logic families.
• Designed for standard TTL voltage levels with defined high and low output current specifications.

Applications

• Decoding binary signals for display drivers in numeric readouts.
• Selecting specific memory addresses or I/O ports in digital systems.
• Controlling sequential operations in industrial automation controllers.

Procurement Notes

Verify that the ordered part matches the exact SN74LS145DR designation to ensure compatibility with LS series logic requirements. Confirm the package type corresponds to the SOIC-16 form factor specified in official documentation. Check for RoHS compliance status if environmental regulations apply to your manufacturing process. Ensure the supplier provides valid traceability documents for quality assurance purposes.

Selection Notes

Choose this component when a direct interface between binary coded decimal data and decimal selection lines is required. The LS series offers a balance of speed and power consumption suitable for general-purpose digital applications. Consider the active-low output polarity when designing the subsequent circuit stage to ensure correct signal interpretation. Verify that the load connected to the open-collector outputs does not exceed the specified current limits.

Part Context

This decoder belongs to the widely adopted 74xx logic family, specifically the Low-power Schottky (LS) variant. The SN74LS145 serves as a foundational building block for converting binary information into selectable decimal states. Its design supports integration into larger digital systems requiring address decoding or control signal distribution without complex external gating.

Replacement Considerations

Compatible substitutes include SN74LS145DRE4 and SN74LS145DRG4. These variants maintain identical logical functionality and pinout configurations while potentially differing in manufacturing lot or specific compliance markings. Cross-reference with SN54145 for military-grade temperature ranges if operating conditions extend beyond commercial limits.