M74HC123B1R

Multivibrators Overview

The M74HC123B1R is a dual retriggerable monostable multivibrator manufactured by STMicroelectronics. It utilizes silicon gate C2MOS technology to achieve high-speed operation comparable to LSTTL while maintaining low CMOS power dissipation. The device features two independent circuits, each with negative edge-triggered (A input) and positive edge-triggered (B input) capabilities. It supports a wide operating voltage range from 2V to 6V and includes direct reset functionality via the CLR input.

Multivibrators Feature Summary

• Dual independent monostable multivibrator circuits fabricated with high-speed silicon gate C2MOS technology
• Retriggerable operation allowing pulse width extension upon subsequent trigger pulses during the timing cycle
• Direct reset capability through the CLR input which forces the output low and rapidly charges the external capacitor
• Symmetrical output impedance and balanced propagation delays for consistent signal timing

Multivibrators Applications

• Pulse generation and timing control in digital systems
• Debouncing of mechanical switches or contacts
• Frequency division and pulse stretching applications
• Timing delay circuits requiring precise duration control via external RC components

Multivibrators Procurement Notes

Verify that the ordering suffix B1R corresponds to the DIP-16 package configuration as specified in the manufacturer's order codes. Confirm compliance with RoHS directives and ensure the component meets the required ambient temperature operating range of -55°C to +125°C for your specific application environment before finalizing procurement.

Multivibrators Selection Notes

Select this component when dual independent monostable timers are required within a single package. Ensure the external resistor and capacitor values selected fall within the recommended limits, particularly noting that Rx should not exceed 1MΩ at 3.0V supply to avoid susceptibility to noise. Consider the wide operating voltage range if system power rails vary between 2V and 6V.

Multivibrators Part Context

This part belongs to the M74HC123 family of dual retriggerable monostable multivibrators. It is functionally compatible with the standard 74LS123 series but offers improved speed and lower power consumption due to its CMOS construction. The B1R suffix indicates the specific tube packaging format for the DIP-16 variant offered by the manufacturer.

Multivibrators Replacement Considerations

Direct functional substitutes include other dual retriggerable monostable multivibrators such as the SN74LS123 or CD74HC123. Verify pin compatibility and electrical specifications, specifically the supply voltage range and output drive current, before implementing any cross-manufacturer replacement.