onsemi MJD44H11TM

Overview

MJD44H11TM from onsemi is an NPN silicon power transistor in DPAK (TO-252) surface-mount package, rated for 8 A continuous collector current, 80 V collector-emitter voltage, and 20 W power dissipation at TC = 25 °C. It delivers low V_CE(sat) of 1 V at I_C = 8 A / I_B = 0.4 A and fast switching with t_d + t_r = 300 ns, designed for output/driver stages in switching regulators, DC-DC converters, and linear power amplifiers.

For engineers reviewing the MJD44H11TM datasheet, pinout, applications, or equivalent options, key selection criteria include its complementary PNP pairing with MJD45H11, AEC-Q101 qualification for automotive-grade reliability, Pb-free RoHS-compliant DPAK-3 footprint, and validated thermal resistance R_θJC = 6.25 °C/W for high-power surface-mount thermal management.

Technical Context

The MJD44H11TM operates as a medium-power NPN bipolar junction transistor optimized for linear and switching operation in high-current, moderate-voltage applications. Its design emphasizes low saturation voltage and fast turn-on/turn-off characteristics, supported by f_T = 85 MHz and C_cb = 45 pF at V_CB = 10 V.

It shares electrical behavior with the legacy D44H series but integrates modern packaging and process enhancements-including UL 94 V-0 epoxy, 150 °C maximum junction temperature, and ESD robustness per HBM Class 3B-enabling use in industrial power stages and automotive auxiliary systems where thermal stability and ruggedness are critical.

Key Specifications

Pinout & Package

DPAK-3 (TO-252) surface-mount package with exposed drain pad (pin 2 and 4 tied internally to collector), 6.10 × 6.54 × 2.28 mm body, 2.29 mm lead pitch, and UL 94 V-0 compliant epoxy molding compound.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN power transistor applications.

Compared with BUW13A and MJD127G, the MJD44H11TM uniquely balances 80 V/8 A rating, 300 ns switching, DPAK surface-mount compatibility, and AEC-Q101 qualification-making it the optimal choice for automotive and industrial switching applications demanding verified reliability and thermal performance in compact layouts.

Availability

MJD44H11TM is available at Aetrix Electronics and suitable for switching regulators, DC motor drivers, and linear audio amplifiers requiring stable component supply, long-term lifecycle support, and automotive-grade traceability.

Supply support for MJD44H11TM 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 specializing in power, analog, sensor, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The MJD44H11TM belongs to onsemi's complementary power transistor family engineered for robust, high-current switching and amplification in space-constrained surface-mount applications-particularly targeting automotive subsystems and industrial power conversion.

FAQ

What is the maximum junction temperature rating for the MJD44H11TM?

The MJD44H11TM has a maximum operating junction temperature of +150 °C, as specified in the Absolute Maximum Ratings table. This rating enables reliable operation in under-hood automotive environments and high-ambient industrial enclosures when mounted on appropriate copper area and heatsinking. Thermal derating begins above 25 °C case temperature, with R_θJC = 6.25 °C/W defining the junction-to-case path. The MJD44H11TM must not exceed this limit to maintain parametric integrity and long-term reliability.

Is the MJD44H11TM pin-compatible with the legacy D44H11 through-hole transistor?

No, the MJD44H11TM is not pin-compatible with the through-hole D44H11. The MJD44H11TM uses a DPAK-3 (TO-252) surface-mount package with four terminals (Base, Collector, Emitter, Collector), while the D44H11 uses a TO-220 package with three leads (Base, Collector, Emitter). Although electrically similar per datasheet Feature section, PCB layout, thermal interface, and assembly process differ fundamentally. The MJD44H11TM requires re-design of footprint, stencil, and thermal relief patterns.

Does the MJD44H11TM require a heatsink in typical applications?

Yes-the MJD44H11TM requires a PCB copper heatsink plane connected to its exposed collector pad (pins 2 and 4) to dissipate up to 20 W at T_C = 25 °C. Without adequate copper area (minimum pad sizes per datasheet Note 1), power dissipation drops to 1.75 W at ambient temperature. For 8 A continuous operation, a ≥ 25 cm² 2-oz copper pour with thermal vias is recommended. The MJD44H11TM's R_θJC = 6.25 °C/W assumes direct thermal contact to an external heatsink or large copper plane.

What is the base drive requirement to fully saturate the MJD44H11TM at 8 A collector current?

To achieve V_CE(sat) ≤ 1 V at I_C = 8 A, the MJD44H11TM requires I_B = 0.4 A, corresponding to a forced beta (I_C/I_B) of 20. This is explicitly defined in the Electrical Characteristics table under "ON CHARACTERISTICS." Base-emitter saturation voltage is ≤ 1.5 V at this condition, so a 5 V logic driver with ≤ 12.5 Ω series resistance (or dedicated base driver IC) is necessary. Undersized base drive increases V_CE(sat), raising power loss and thermal stress on the MJD44H11TM.

Is the MJD44H11TM suitable for use in Class D audio amplifier output stages?

No-the MJD44H11TM is not optimized for Class D audio output stages. Its 85 MHz f_T and 300 ns switching times are adequate for ~200–300 kHz operation, but Class D amplifiers typically demand faster devices (f_T > 150 MHz, t_f < 50 ns) and lower C_cb to minimize dead-time distortion and EMI. The MJD44H11TM's 45 pF C_cb and lack of optimized gate charge characteristics make it better suited for Class AB, switching regulators, and motor drives-not high-frequency PWM audio output.