onsemi 74LCX02MX

Overview

74LCX02MX from onsemi is a low-voltage quad 2-input NOR gate IC with 5 V tolerant inputs, designed for level-shifting between 3 V and 5 V logic systems. It operates across 1.65 V–5.5 V V_CC, delivers ≤5.2 ns propagation delay at 3.3 V, supports ±24 mA output drive, and features power-down high-impedance I/O for bus-hold compatibility in mixed-voltage embedded control interfaces.

For engineers reviewing the 74LCX02MX datasheet, pinout, applications, or equivalent options, key selection criteria include 5 V input tolerance, sub-6 ns t_PD at 3.3 V, ±24 mA drive strength, thermal performance up to +125 °C, and TSSOP-14 WB package compatibility with automated SMT assembly.

Technical Context

The 74LCX02MX implements four independent 2-input NOR gates using advanced CMOS process technology optimized for high-speed, low-power operation. Its input structure tolerates up to 5.5 V regardless of V_CC, enabling direct interfacing between legacy 5 V peripherals and modern 3.3 V microcontrollers without external level shifters.

Each gate provides rail-to-rail output swing, active-mode drive capability up to ±24 mA at V_CC = 3.0 V, and guaranteed high-impedance behavior during power-down (V_CC = 0 V). Propagation delay is specified down to 4.2 ns at 5 V and remains ≤5.2 ns at 3.3 V across −40 °C to +125 °C.

Key Specifications

Pinout & Package

TSSOP-14 WB (Case 948G), 4.9 mm × 4.4 mm body, 0.65 mm pitch, 1.2 mm max height, Pb-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NOR gate logic applications.

Compared with SN74LVC02APWR and 74AHC02PW,118, the 74LCX02MX uniquely combines 5 V input tolerance, sub-6 ns speed at 3.3 V, and ±24 mA drive in a TSSOP-14 package - making it the only option among the three that eliminates external level shifters while maintaining timing integrity in mixed-voltage control logic.

Availability

74LCX02MX is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, medical infusion pump safety logic, IoT edge gateway interface bridging, and embedded system level-shifting applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74LCX02MX 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 innovation for automotive, industrial, cloud, and medical applications.

The 74LCX02MX belongs to the LCX family of low-voltage, high-speed CMOS logic devices engineered specifically for mixed-voltage system interfacing and noise-sensitive embedded control environments.

FAQ

What is the maximum input voltage the 74LCX02MX can tolerate?

The 74LCX02MX supports DC input voltages up to 5.5 V regardless of V_CC level - a key feature enabling direct connection to 5 V buses while operating from 3.3 V or lower supplies. This eliminates the need for external clamping diodes or level translators in mixed-voltage designs, and is explicitly verified in the Absolute Maximum Ratings table of the official onsemi datasheet (Rev. 2, November 2024).

Does the 74LCX02MX support operation at 1.8 V V_CC?

Yes, the 74LCX02MX is fully specified for operation at 1.65 V to 5.5 V V_CC, including 1.8 V. At 1.8 V, the device maintains functional logic behavior with VIH/VIL thresholds defined as 0.65×V_CC and 0.35×V_CC, respectively, and propagation delay increases to ≤10.3 ns per the AC Electrical Characteristics table - making it suitable for ultra-low-power portable and battery-operated systems.

Can the 74LCX02MX outputs drive LEDs directly?

Yes, the 74LCX02MX outputs can drive standard indicator LEDs directly: at V_CC = 3.0 V, each output provides up to 24 mA sink/source current, sufficient for typical 2–20 mA LED configurations. For common-anode setups, connect the LED anode to V_CC and cathode to an output pin; for common-cathode, reverse the connection and use the NOR gate's active-low output behavior to illuminate on logic low.

Is the 74LCX02MX pin-compatible with other 74-series NOR gates in TSSOP-14?

No - the 74LCX02MX uses standard 74-series pinout for quad 2-input NOR gates (e.g., pins 1–2–3 for first gate, 4–5–6 for second, etc.), but its 5 V tolerant inputs and power-down high-Z behavior are not shared by legacy 74HC02 or 74HCT02 in the same package. While physical pin alignment matches, electrical behavior differs significantly; substitution requires validation of input voltage compatibility and power-state behavior in the target design.

What is the thermal resistance (θ_JA) of the 74LCX02MX in TSSOP-14 WB package?

The 74LCX02MX in TSSOP-14 WB (Case 948G) has a junction-to-ambient thermal resistance (θ_JA) of 150 °C/W, measured per JESD51-7 on a 76 mm × 114 mm, 2-ounce copper FR4 board with no airflow. This value supports continuous operation up to +125 °C ambient when power dissipation remains below 833 mW, as confirmed in the Absolute Maximum Ratings section of the onsemi datasheet.