STMicroelectronics M74HC109M1R

Overview

M74HC109M1R from STMicroelectronics is a high-speed CMOS dual J-K flip-flop with asynchronous preset and clear, fabricated in silicon gate C2MOS technology. It operates across 2V–6V, delivers 67MHz max clock frequency (typ. at VCC=6V), features symmetrical 4mA output drive, and is pin/function compatible with standard 74-series 109 logic. Used in synchronous digital control circuits requiring edge-triggered state storage with independent set/reset.

For engineers reviewing the M74HC109M1R datasheet, M74HC109M1R pinout, M74HC109M1R application, or M74HC109M1R equivalent, key selection criteria include propagation delay matching (tPLH/tPHL ≈ 13–26 ns at 6V), low ICC (2µA max at 25°C), wide VCC range (2–6V), and guaranteed noise immunity (VNIH/VNIL ≥ 28% VCC).

Technical Context

The M74HC109M1R implements two independent edge-triggered J-K flip-flops, each with active-low asynchronous preset (1PR/2PR) and clear (1CLR/2CLR) inputs that override clock and data. State changes occur on the positive-going transition of CK, with J/K inputs sampled synchronously.

Its C2MOS process enables rail-to-rail input voltage tolerance (VI = 0 to VCC), balanced output impedance (|IOH| = IOL ≥ 4mA), and low quiescent current (ICC ≤ 2µA at TA = 25°C), supporting robust operation in mixed-voltage digital systems from 2V to 6V.

Key Specifications

Pinout & Package

Package: SO-16 (Small Outline Integrated Circuit, 150 mil width), compliant with JEDEC MS-013, body dimensions 9.8 × 5.8 mm, lead pitch 1.27 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual J-K flip-flop applications.

Compared with SN74HC109DR and 74HC109D,653, the M74HC109M1R offers the lowest quiescent current (2 µA max at 25°C) and highest verified fMAX (67 MHz), making it optimal for low-power, high-speed synchronous logic where thermal headroom and timing margin are critical.

Availability

M74HC109M1R is available at Aetrix Electronics and suitable for industrial PLC counter modules, digital signal generator control, automotive body control unit sequencers, and test equipment pattern generators requiring stable component supply across extended temperature ranges (–55°C to +125°C).

Supply support for M74HC109M1R 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, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The M74HC109M1R belongs to ST's high-speed CMOS logic family, engineered for compatibility with legacy TTL systems while delivering ultra-low power and enhanced noise immunity in industrial and automotive control applications.

FAQ

What is the maximum operating temperature range for the M74HC109M1R?

The M74HC109M1R is rated for operation from –55°C to +125°C, validated per STMicroelectronics' recommended operating conditions. This full industrial temperature range ensures reliability in under-hood automotive environments and uncooled industrial enclosures, with all DC and AC parameters guaranteed across this span.

Can the M74HC109M1R operate reliably at 3.3V supply?

Yes - the device is fully specified from 2V to 6V, including 3.3V. At VCC = 3.3V, VIH is guaranteed ≥ 2.31V and VIL ≤ 0.99V, providing >0.6V noise margin. Propagation delay increases to ~38 ns (max), and output drive drops to ~2.5 mA, which remains sufficient for driving HC/HCT loads.

Is there a TSSOP variant of this part, and how does it differ electrically?

Yes - the M74HC109TTR is the TSSOP-16 variant. Electrically identical in all DC/AC specifications, including fMAX, propagation delay, and drive strength. The only differences are mechanical: smaller footprint (5.0 × 6.4 mm), finer pitch (0.65 mm), and lower thermal resistance (θJA ≈ 140°C/W vs. 100°C/W for SO-16), requiring adjusted PCB layout and reflow profile.

Does the M74HC109M1R require external pull-up resistors on PR/CLR inputs?

No - PR and CLR are active-low inputs with internal protection diodes and no internal pull-ups. When left unconnected, they float high due to input leakage (±0.1 µA), but ST recommends tying unused PR/CLR pins to VCC via 10 kΩ resistors to prevent noise-induced glitches, especially in high-noise environments.