SN74LS145D

Overview

The SN74LS145D is a BCD-to-decimal decoder/driver from the Texas Instruments LS series, housed in a 16-pin SOIC package. It features four binary inputs and ten active-low open-collector outputs. The device operates on a single 5 V supply (4.75 V to 5.25 V) with a propagation delay of 50 ns. It supports a bandwidth of 35 MHz and draws 1 mA of supply current. The component functions as an inverting logic circuit within a commercial 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
• Features open-collector outputs suitable for driving external loads or wired-AND configurations
• Provides high noise immunity and temperature compensation inherent to the LS TTL technology

Applications

• Decoding binary signals for display drivers
• Control logic in industrial automation systems
• Address decoding in memory subsystems

Procurement Notes

Verify the specific suffix 'D' confirms the SOIC surface-mount package variant rather than the PDIP through-hole version. Confirm RoHS compliance status as manufacturing sources may vary by production date. Ensure the supplier provides original manufacturer documentation to validate the LS logic family specifications and electrical characteristics against the official datasheet.

Selection Notes

Select this component when a compact surface-mount solution is required for BCD-to-decimal conversion. The LS series offers a balance of speed and power consumption compared to standard TTL. Verify that the application can accommodate the open-collector output requirement and the necessary pull-up resistors for proper logic level restoration.

Part Context

This part belongs to the Texas Instruments 74LS logic family, designed for low-power Schottky applications. It serves as a functional equivalent to other industry-standard BCD decoders like the SN54145, adapted for commercial temperature ranges and specific packaging requirements. The device is integral to digital systems requiring direct interface between binary data and decimal indicators.

Replacement Considerations

Compatible substitutes include the SN74LS145N (PDIP package) and SN74LS145NSRG4 (SOIC package). Cross-reference with SN54145 for military-grade temperature specifications if required.