TC74AC138P(F)

Overview

The TC74AC138P(F) is a CMOS logic decoder manufactured by Toshiba Semiconductor and Storage. It implements a 3-to-8 line decoding function within the AC logic series. The component utilizes silicon gate and double-layer metal wiring CMOS technology to achieve high-speed operation comparable to Bipolar Schottky TTL while maintaining low power dissipation. It features active-low outputs and includes input protection circuits against electrostatic discharge. The device operates on a single power supply ranging from 2 V to 5.5 V, with a maximum propagation delay of 13.9 ns at 3.3 V under a 50 pF load condition.

Feature Summary

• Provides 3-to-8 line decoding functionality using advanced CMOS technology
• Features active-low outputs for direct interfacing with control logic
• Includes input protection circuits designed to withstand electrostatic discharge

Applications

• Address decoding in microprocessor-based systems
• Memory chip select generation
• Control signal routing in digital logic circuits

Procurement Notes

Verify the specific suffix designation (P or F) to confirm the package type, as P indicates PDIP and F indicates SOP. Confirm RoHS compliance status through official datasheets or manufacturer declarations before integration. Ensure voltage levels match system requirements within the 2 V to 5.5 V operating range. Check for updated revision history regarding pinout or electrical characteristics changes.

Selection Notes

Select this component when a 3-to-8 decoder is required with AC-series speed and CMOS power efficiency. Verify that the system voltage falls within the specified 2 V to 5.5 V range. Consider the PDIP package for through-hole mounting if indicated by the suffix. Ensure input signals are compatible with CMOS logic thresholds. Evaluate thermal performance if operating near maximum temperature limits.

Part Context

This part belongs to the Toshiba TC74AC series of advanced high-speed CMOS logic integrated circuits. The AC series is designed to offer performance similar to Bipolar Schottky TTL but with significantly lower power consumption. This specific model functions as a decoder, distinguishing it from buffers, gates, or flip-flops within the same logical family.

Replacement Considerations

Cross-reference with other 3-to-8 decoders from the 74AC series such as those from NXP or ON Semiconductor. Verify pin compatibility and electrical specifications like propagation delay and output drive current. Ensure the replacement supports the same voltage range and package type if physical constraints exist.