onsemi MM74HC244MTC

Overview

MM74HC244MTC from ON Semiconductor is an octal non-inverting 3-STATE buffer with dual active-low enables (1G, 2G), each controlling four independent buffers. It operates across 2–6 V, delivers 6 mA output drive, exhibits 14 ns typical propagation delay at 4.5 V, and supports bus interfacing in industrial control and digital logic systems.

For engineers reviewing the MM74HC244MTC datasheet, pinout, applications, or equivalent options, key selection criteria include 3-STATE bus drive capability, wide supply range compatibility, low quiescent current (80 µA), high noise immunity, and TSSOP-20 packaging for space-constrained PCB layouts.

Technical Context

The MM74HC244MTC implements eight CMOS-based non-inverting buffer stages grouped into two quad sections, each controlled by a dedicated active-low enable input (1G, 2G). Its outputs enter high-impedance state when the respective enable is HIGH, enabling bidirectional bus sharing without external logic.

Designed using advanced silicon-gate CMOS technology, it achieves LS-TTL-compatible speed (20 ns max propagation delay at 4.5 V) while maintaining CMOS advantages: high noise margin (>40% of VCC), low static power consumption, and input protection diodes to VCC and GND.

Key Specifications

Pinout & Package

MM74HC244MTC is housed in a 20-lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153 compliant, 4.4 mm body width, 0.65 mm lead pitch, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal non-inverting buffer applications.

Compared with SN74HC244N and 74HC244PW, the MM74HC244MTC offers identical functional behavior and TSSOP-20 mechanical compatibility but originates from ON Semiconductor's post-Fairchild integration lineage, ensuring long-term supply continuity and documented industrial temperature validation (−40°C to +85°C).

Availability

MM74HC244MTC is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, legacy bus interface adapters, and embedded system address latch drivers requiring stable component supply across extended product lifecycles.

Supply support for MM74HC244MTC 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensors, and logic solutions for automotive, industrial, cloud, and consumer markets.

The MM74HC244MTC belongs to ON Semiconductor's legacy HC logic family, designed for robust, low-power digital interfacing in industrial control, instrumentation, and embedded systems where reliability and wide supply tolerance are essential.

FAQ

What is the maximum operating temperature range for the MM74HC244MTC?

The MM74HC244MTC is rated for operation from −40°C to +85°C ambient temperature. This industrial-grade range is validated per the manufacturer's recommended operating conditions and applies specifically to the MTC20 TSSOP package. Thermal derating is not required within this span, and all DC and AC specifications are guaranteed across the full range. The MM74HC244MTC maintains stable 3-STATE behavior and propagation delay consistency under these conditions.

Does the MM74HC244MTC support 3.3 V logic systems?

Yes, the MM74HC244MTC fully supports 3.3 V operation. Its supply voltage range is 2.0–6.0 V, and all electrical characteristics-including VOH (≥3.84 V), VOL (≤0.33 V), and VIH (≥2.0 V) at VCC = 3.3 V-are specified and tested. Input thresholds scale with VCC, ensuring reliable recognition of 3.3 V logic levels. The MM74HC244MTC is commonly used to buffer 3.3 V microcontroller GPIOs driving higher-capacitance loads.

What is the purpose of the two enable inputs (1G and 2G) on the MM74HC244MTC?

The MM74HC244MTC features two independent active-low enable inputs: 1G controls Y1–Y4, and 2G controls Y5–Y8. When an enable is LOW, its associated four outputs actively drive their inputs; when HIGH, those outputs enter high-impedance state. This allows selective gating of two 4-bit data groups-enabling applications like dual-bus arbitration, partial address latching, or interleaved peripheral access without external logic. The MM74HC244MTC does not require both enables to be asserted simultaneously.

Is the MM74HC244MTC pin-compatible with other HC-series octal buffers?

Yes, the MM74HC244MTC is pin-compatible with industry-standard octal 3-STATE non-inverting buffers in TSSOP-20 packages, including the 74HC244PW and MC74HC244ADTR2G. Pin assignments for VCC, GND, enables (1G/2G), inputs (A1–A8), and outputs (Y1–Y8) follow JEDEC MO-153 layout conventions. However, always verify timing parameters and thermal characteristics, as process variations may affect enable/disable delays. The MM74HC244MTC retains identical pinout across all Fairchild/ON Semiconductor HC244 variants in MTC20 packaging.

What is the typical power dissipation of the MM74HC244MTC under active operation?

Under typical active operation (all outputs driving 6 mA loads at 4.5 V), the MM74HC244MTC dissipates approximately 27 mW per buffer (216 mW total), calculated from CPD = 12 pF, VCC = 4.5 V, and f = 10 MHz. Static dissipation is negligible (≤80 µA × 4.5 V ≈ 0.36 mW). Total power remains well below the TSSOP-20 package's 500 mW limit, even with all eight buffers active and moderate capacitive loading. The MM74HC244MTC requires no heatsinking in standard industrial airflow environments.