onsemi MC74VHC32MELG

Overview

MC74VHC32MELG from onsemi is a high-speed CMOS quad 2-input OR gate in SOIC-14 package, operating from 2.0 V to 5.5 V with 3.8 ns typical propagation delay at 5.0 V, 15 pF load, and full 5.0 V CMOS-level output swing. It serves as a logic-level translator between 3.3 V and 5.0 V systems and provides high noise immunity (28% VCC) in industrial control and embedded interface circuits.

For engineers reviewing the MC74VHC32MELG datasheet, pinout, applications, or equivalent options, key selection criteria include input voltage compatibility (CMOS-level), output drive capability (±8 mA), thermal resistance (116 °C/W), latchup immunity (>100 mA), and Pb-free RoHS compliance per AEC-Q100 qualified variants.

Technical Context

The MC74VHC32MELG implements four independent OR gates (Y = A + B) using silicon-gate CMOS technology, achieving TTL-compatible speed without bipolar power penalties. Its three-stage internal architecture includes a buffered output stage for stable switching and high noise margin.

Input structures tolerate up to 5.5 V, enabling safe interfacing of 5 V systems to 3 V logic domains. The device lacks tristate or power-down control features - all outputs are actively driven in both logic states, with no high-impedance mode.

Key Specifications

Pinout & Package

MC74VHC32MELG is packaged in SOIC-14 (Case 751A), 8.75 mm × 4.00 mm body, 1.75 mm height, with 1.27 mm pitch and Pb-free matte tin lead finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input OR gate applications.

Compared with SN74LVC32APWR and 74AHC32D,118, the MC74VHC32MELG offers superior noise immunity (28% vs. 20% VCC), tighter propagation delay matching across gates, and guaranteed 5.5 V input tolerance - making it optimal for legacy 5 V system integration where signal integrity under EMI stress is critical.

Availability

MC74VHC32MELG is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, medical power sequencing, and test equipment signal conditioning requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MC74VHC32MELG 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, delivering silicon-based solutions for automotive, industrial, cloud, and IoT applications.

The MC74VHC32MELG belongs to the VHC (Very High Speed CMOS) logic family, designed specifically for high-speed, low-power digital interfacing in mixed-voltage embedded systems where TTL-speed performance and CMOS efficiency must coexist.

FAQ

What is the maximum input voltage tolerance for MC74VHC32MELG?

The MC74VHC32MELG supports DC input voltages up to 5.5 V regardless of VCC level, enabling safe interfacing between 5 V sensors and lower-voltage logic rails. This specification is verified per the Absolute Maximum Ratings table in the official datasheet, where Vin is rated −0.5 V to +6.5 V - but functional operation above 5.5 V is not guaranteed. The MC74VHC32MELG maintains correct logic behavior and avoids damage when inputs exceed VCC, a key advantage over standard TTL or LVC devices.

Does MC74VHC32MELG support tristate or high-impedance outputs?

No, the MC74VHC32MELG does not support tristate or high-impedance outputs. All four OR gates provide actively driven push-pull outputs in both logic states, with no enable or output-control pins. This is confirmed by the absence of OE (output enable), EN, or Z-state specifications in the Functional Table, AC Characteristics, and Pin Description sections of the datasheet. For bus-sharing applications requiring high-impedance control, designers must select an alternative part such as the MC74VHC240 or SN74LVC244.

What is the thermal resistance (θJA) of MC74VHC32MELG in its SOIC-14 package?

The MC74VHC32MELG in SOIC-14 package has a junction-to-ambient thermal resistance (θJA) of 116 °C/W, measured under JEDEC-standard conditions (76 mm × 114 mm, 2-ounce copper, no airflow). This value is specified in the Maximum Ratings table on page 2 of the datasheet and reflects worst-case still-air dissipation. At 5.5 V and full output loading, total power dissipation remains below 15 mW per gate, keeping junction temperature rise well within safe limits even in compact enclosures.

Can MC74VHC32MELG be used as a level shifter between 3.3 V and 5.0 V systems?

Yes, the MC74VHC32MELG can serve as a unidirectional level shifter from 3.3 V inputs to 5.0 V outputs. Its CMOS-compatible inputs accept 3.3 V logic highs (VIH ≥ 2.31 V at VCC = 3.3 V), and its outputs swing rail-to-rail (VOH ≥ 4.4 V, VOL ≤ 0.1 V at VCC = 5.0 V), satisfying 5 V TTL and CMOS input thresholds. However, it does not translate 5 V inputs down to 3.3 V logic levels - for bidirectional translation, a dedicated level-shifting IC or resistor-based solution is required.

Is MC74VHC32MELG qualified for automotive applications?

The base MC74VHC32MELG is not automotive-qualified; however, onsemi offers the MC74VHC32DR2G−Q variant, which carries the −Q suffix, is AEC-Q100 qualified, and supports PPAP documentation. The MC74VHC32MELG itself shares identical electrical and thermal specifications but lacks the controlled manufacturing site, change control, and extended temperature validation required for automotive use. Customers requiring automotive-grade assurance must specify the −Q suffix version during procurement.