74HCT5555D,112

Overview

The 74HCT5555D,112 is a precision programmable delay timer manufactured by Nexperia. It integrates a 24-stage binary counter, an oscillator using external timing components, and a retriggerable or non-retriggerable monostable circuit. The device operates on a supply voltage range of 2.0 V to 6.0 V with CMOS input levels. Key features include positive and negative edge triggering, Schmitt trigger action on inputs, and three oscillator modes: RC, crystal, and external clock. It provides a divide-by range from 2 to 2^24 and includes automatic power-on reset functionality.

Feature Summary

• Programmable delay timer with a 24-stage binary counter and divide-by range of 2 to 2^24
• Supports RC, crystal, and external oscillator operating modes for flexible timing control
• Features Schmitt trigger inputs for noise immunity and direct drive capability for power transistors
• Includes automatic power-on reset and overriding asynchronous master reset (MR)

Applications

• Motor control systems
• Precision timing circuits
• Delay circuits
• Domestic appliances

Procurement Notes

Verify the ordering suffix '112' against official Nexperia documentation to confirm specific tape-and-reel packaging details. Ensure the SO16 package type matches the design requirements. Confirm temperature range specifications (-40 °C to +125 °C) align with the intended operational environment before procurement.

Selection Notes

Select this component when precise digital timing delays are required with high accuracy. Consider the HCT logic family for compatibility with TTL-level interfaces. Evaluate the need for retriggerable versus non-retriggerable operation based on the application's pulse extension requirements. Ensure external timing components meet the specified resistance and capacitance limits for the desired frequency range.

Part Context

This part belongs to the 74HC/HCT5555 series of programmable delay timers. It is pin-compatible with low-power Schottky TTL (LSTTL) devices. The datasheet revision is Rev. 4, dated 5 July 2018. The manufacturer is Nexperia B.V., which acquired the relevant business from NXP Semiconductors.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided source material.