CD74HCT147E

Overview

The CD74HCT147E is a high-speed CMOS logic device manufactured by Harris Corporation, functioning as a 10-line-to-4-line priority encoder. It utilizes silicon gate CMOS technology and operates within a supply voltage range of 4.5V to 5.5V. The component features low power dissipation and provides direct compatibility with Low-power Schottky TTL (LSTTL) inputs. It is housed in a standard 16-pin Plastic Dual In-Line Package (PDIP16).

Feature Summary

• Implements 10-line-to-4-line priority encoding using active-low inputs and outputs.
• Features direct pin compatibility with LSTTL logic families for seamless integration.
• Utilizes high-speed silicon gate CMOS technology for efficient operation.

Applications

• Encoding decimal or hexadecimal data into binary codes for digital systems.
• Keyboard encoding applications requiring priority handling of multiple input signals.
• Interface circuits between LSTTL-compatible devices and CMOS logic blocks.

Procurement Notes

Verify the manufacturer designation on the component marking, as production has transferred from Harris Corporation to Texas Instruments. Confirm that the specific part number suffix corresponds to the PDIP16 package type. Ensure compliance with current environmental regulations, noting that older Harris-branded units may not meet modern RoHS standards compared to newer TI equivalents.

Selection Notes

Select this component when a priority encoder is required that maintains electrical compatibility with existing LSTTL designs while benefiting from CMOS noise immunity. The HCT series ensures proper logic level translation without additional interface components. Consider the PDIP16 package constraints regarding board space and thermal management during the design phase.

Part Context

This device belongs to the 74HCT logic family, which bridges the gap between standard CMOS performance and TTL compatibility. Originally developed by Harris Semiconductor, these parts were widely adopted before the division's acquisition by Texas Instruments. The CD74HCT147E represents a legacy industrial standard for priority encoding functions in mixed-logic environments.

Replacement Considerations

Texas Instruments offers equivalent parts such as the CD74HC147E and CD74HCT147E. Verify that the replacement source explicitly supports the HCT logic family to maintain LSTTL input compatibility. Check if the new manufacturer's datasheet confirms identical pinout and functional specifications for the DIP-16 package.