STMicroelectronics HCF4098BEY

Overview

HCF4098BEY from STMicroelectronics is a dual retriggerable/resettable monostable multivibrator in 16-pin DIP package, operating from 3 V to 20 V supply. It delivers precision one-shot timing with independent trigger/reset propagation delays (e.g., 100–500 ns), buffered Q/Q̅ outputs per channel, and external RC control (RX ≥ 5 kΩ, CX ≤ 100 µF) enabling pulse widths from microseconds to seconds. Used in digital timing control, debounce circuits, and pulse shaping in industrial logic systems.

For engineers reviewing the HCF4098BEY datasheet, HCF4098BEY pinout, HCF4098BEY application, or HCF4098BEY equivalent, key selection criteria include retriggerability mode configuration, edge-triggering flexibility (+TR/-TR), reset polarity (active-low), output drive capability (±1.3 mA at VDD = 5 V), and temperature-stable pulse width accuracy (±2.5% over –55 °C to +125 °C).

Technical Context

The HCF4098BEY implements two independent CMOS monostable sections, each supporting both leading-edge (+TR) and trailing-edge (–TR) triggering via separate inputs. Trigger and reset propagation delays are decoupled from external RC timing components, ensuring consistent timing behavior across voltage and temperature.

Each section features active-low asynchronous RESET, buffered complementary Q/Q̅ outputs, and configurable retriggerable or non-retriggerable operation via internal feedback routing (e.g., Q→–TR for leading-edge non-retriggerable mode). Timing equation T = 0.5 × RX × CX applies for CX > 0.01 µF, with guaranteed stability over JEDEC B-series specifications.

Key Specifications

Pinout & Package

Package: 16-pin plastic DIP (0.3-inch width), JEDEC MS-001, body dimensions 20.0 × 8.5 mm, lead pitch 2.54 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual monostable multivibrator applications.

Compared with CD4098BE and 74HC4538N, the HCF4098BEY offers unique retriggerable operation with independent edge-select inputs and superior voltage range - making it optimal for adaptive timing in industrial control and robust power-on sequencing.

Availability

HCF4098BEY is available at Aetrix Electronics and suitable for industrial pushbutton debounce, digital signal edge detection, and power-on reset sequencing requiring stable component supply across extended temperature and voltage ranges.

Supply support for HCF4098BEY includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with strong analog/mixed-signal heritage.

The HCF4098B belongs to ST's legacy CMOS logic family designed for high-reliability timing applications in industrial automation, instrumentation, and embedded control - emphasizing wide-voltage operation, temperature stability, and JEDEC-compliant robustness.

FAQ

What is the minimum external resistor value for stable timing with HCF4098BEY?

The minimum external resistor (RX) is 5 kΩ, as specified in the datasheet. Using lower values risks excessive current draw through the internal timing path, increased power dissipation, and potential timing inaccuracy due to internal node loading. At VDD = 20 V, RX < 5 kΩ may exceed safe power limits per output transistor (100 mW).

How do I configure HCF4098BEY for non-retriggerable operation?

For non-retriggerable mode using leading-edge trigger (+TR), connect Q output to the –TR input of the same section. For trailing-edge trigger (–TR), connect Q to +TR. This feedback forces the monostable to ignore subsequent triggers until the current pulse completes, establishing fixed-duration output independent of input frequency.

Can HCF4098BEY operate reliably at –55 °C?

Yes - the device is fully characterized from –55 °C to +125 °C. Pulse width accuracy remains within ±2.5% at –55 °C when CX = 1000 pF and RX = 100 kΩ, and quiescent current stays below 30 µA at VDD = 5 V. All DC and dynamic parameters meet specification across this full range.

What is the purpose of tying unused –TR inputs to VDD?

Tying unused –TR inputs to VDD holds them at a logic-high level, preventing floating nodes that could cause unintended triggering from noise. Since –TR responds to falling edges, a static high state disables its function safely - unlike +TR, which must be tied to VSS (logic-low) to avoid spurious rising-edge detection.