74HC4538D

Overview

The Toshiba 74HC4538D is a dual retriggerable precision monostable multivibrator fabricated with silicon gate C2MOS technology. It operates within a supply voltage range of 2.0 to 6.0 V and features Schmitt trigger inputs for slow rise/fall time signals. The device provides positive edge (A) and negative edge (B) triggering, along with a reset input (CD). It achieves high-speed operation similar to LSTTL while maintaining low power dissipation, with typical propagation delays of 25 ns at 5 V.

Feature Summary

• Dual retriggerable precision monostable multivibrator architecture
• Schmitt trigger inputs compatible with slow rise/fall time signals
• Balanced propagation delays between high-to-low and low-to-high transitions
• Wide operating voltage range from 2.0 V to 6.0 V

Applications

• Pulse generation circuits
• Timing delay applications
• Debouncing switches
• Frequency division circuits

Procurement Notes

Verify the specific manufacturer lot and revision level against the latest Toshiba Semiconductor datasheet Rev.6.0. Confirm that the SOIC-16 package dimensions match your PCB footprint requirements. Ensure external resistor and capacitor values adhere to the specified operating ranges for the target supply voltage to guarantee proper functionality.

Selection Notes

Select this component when a dual-channel monostable multivibrator with Schmitt trigger inputs is required. It is suitable for designs needing balanced propagation delays and wide voltage compatibility. Consider the external timing components' leakage characteristics, as they influence the maximum allowable resistance values for stable pulse width generation.

Part Context

This part belongs to the 74HC series of CMOS digital integrated circuits. It is functionally equivalent to other standard monostable multivibrators in the industry but utilizes Toshiba's specific C2MOS fabrication process. The device is designed to replace older logic families while offering improved noise immunity and lower power consumption.

Replacement Considerations

Check pinout compatibility with existing designs. Verify that alternative manufacturers' parts meet the same electrical specifications, particularly the Schmitt trigger thresholds and propagation delays. Ensure the replacement package matches the SOIC-16 form factor.