Diodes Incorporated ZXTCM322TA

Overview

ZXTCM322TA from Diodes Incorporated (formerly Zetex) is a 50V NPN low-saturation transistor in a 2mm × 2mm MLP package, delivering V_CE(sat) ≤ 145 mV at 4A/200mA drive, h_FE ≥ 200 at 1A, and R_θJA = 42°C/W on 65 cm² 2oz copper - optimized for high-efficiency DC-DC converters, motor control switches, and battery charging circuits.

For engineers reviewing the ZXTCM322TA datasheet, ZXTCM322TA pinout, ZXTCM322TA application, or ZXTCM322TA equivalent, key selection criteria include verified low V_CE(sat) performance across 0.1–4A load range, thermal derating behavior under varying PCB copper area, and compatibility with space-constrained power switch layouts requiring <0.9 mm profile height.

Technical Context

This NPN bipolar junction transistor employs a fourth-generation epitaxial process to achieve ultra-low saturation voltage while maintaining robust secondary breakdown immunity. Its design targets switching-mode power applications where conduction loss dominates thermal budget - especially in synchronous rectifier and high-side driver roles where base drive efficiency and thermal coupling to PCB are critical.

The device's MLP322 package integrates an exposed thermal pad directly bonded to the collector, enabling low-junction-to-ambient resistance (as low as 42°C/W) when mounted on ≥65 cm² of 2oz copper. Electrical characteristics are specified under pulsed conditions (300 µs, ≤2% duty cycle), ensuring stable gain (h_FE = 100–450) and transition frequency (f_T = 100–165 MHz) across –55°C to +150°C operating range.

Key Specifications

Pinout & Package

Package: MLP322 (2mm × 2mm Micro Leaded Package), single-die, exposed thermal pad connected to collector terminal. Nominal height 0.9 mm; 0.65 mm pitch; 3-pin configuration with pin 1 (Emitter), pin 2 (Base), pin 3 (Collector/thermal pad).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-saturation NPN transistor applications.

Compared with ZXTN619MA and DMT3006LPSQ-13, ZXTCM322TA offers the highest continuous current rating (4A) and lowest thermal resistance in its class, making it optimal for thermally constrained 24–48V DC-DC and motor drive applications where sustained conduction loss must remain below 1.2 W.

Availability

ZXTCM322TA is available at Aetrix Electronics and suitable for DC-DC converters, battery charging circuits, and motor control systems requiring stable component supply and long-term lifecycle continuity.

Supply support for ZXTCM322TA 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

Diodes Incorporated acquired Zetex Semiconductors in 2008 and maintains its portfolio of high-performance discrete transistors and analog ICs for power management and signal conditioning.

The ZXTCM series belongs to Zetex's Miniature Package Power Solutions (MPPS™) line, engineered specifically for space- and thermally constrained switching applications in portable, automotive, and industrial equipment.

FAQ

What is the maximum continuous collector current for ZXTCM322TA under standard PCB conditions?

The ZXTCM322TA supports 4A continuous collector current when mounted on ≥65 cm² of 2oz copper (R_θJA = 42°C/W). At 25°C ambient, this allows 2.45 W dissipation before reaching the 150°C max junction temperature. Derating is required above 25°C per the 19.6 mW/°C linear factor specified in the datasheet.

Does ZXTCM322TA require a heatsink for 4A operation?

No external heatsink is required if the MLP322 package is soldered to a minimum 1.22 mm × 1.42 mm exposed copper area connected to ≥65 cm² of 2oz internal or external PCB copper. The thermal pad (pin 3) must be fully reflowed to achieve the 42°C/W R_θJA; using less copper increases thermal resistance and mandates current derating.

How does the h_FE vary with collector current and temperature?

h_FE ranges from 400 at IC = 10 mA to 40 at IC = 6 A (V_CE = 2 V), with minimal variation across –55°C to +100°C. At 100°C, h_FE remains ≥70% of its 25°C value at 1A, supporting stable saturation in high-temperature motor control environments.

Is ZXTCM322TA pin-compatible with ZXTN619MA?

Yes - both devices use identical MLP322 (2mm × 2mm) package with matching pin 1 (E), pin 2 (B), pin 3 (C) assignment and thermal pad layout. ZXTN619MA replaces ZXTCM322TA as the recommended successor, offering improved V_CEO (60V) and tighter V_CE(sat) distribution while maintaining full mechanical and solder-reflow compatibility.