STMicroelectronics MJD44H11T4

Overview

MJD44H11T4 from STMicroelectronics is an NPN low-voltage complementary power transistor in DPAK (TO-252) package, rated for 80 V V_CEO, 8 A continuous collector current, and 20 W total power dissipation at T_C = 25°C; it delivers low 1 V V_CE(sat) at I_C = 8 A / I_B = 0.4 A and supports general-purpose linear amplification and hard-switching applications in industrial motor drives and DC-DC converters.

For engineers reviewing the MJD44H11T4 datasheet, MJD44H11T4 pinout, MJD44H11T4 application, or MJD44H11T4 equivalent, key selection criteria include verified V_CE(sat) ≤ 1 V at high I_C, h_FE ≥ 40 at 4 A, thermal resistance R_thJC = 6.25 °C/W, safe operating area compliance per Figure 1, and DPAK footprint compatibility with TO-252 type C2 land pattern.

Technical Context

This NPN bipolar junction transistor uses multi-epitaxial planar technology optimized for low-saturation switching and stable DC gain across temperature. It operates with V_CEO = 80 V, I_C = 8 A, and supports pulsed peak current up to 16 A under ≤ 2% duty cycle conditions.

Thermal design is enabled by a low R_thJC of 6.25 °C/W and maximum junction temperature of 150°C, while electrical behavior is characterized at T_C = 25°C with guaranteed h_FE ≥ 60 at I_C = 2 A and ≥ 40 at I_C = 4 A - enabling predictable biasing in Class AB amplifiers and robust gate driving in discrete half-bridge stages.

Key Specifications

Pinout & Package

Package: DPAK (TO-252) type C2 - surface-mount, single-ended power package with exposed drain tab (pin 2) for thermal and electrical connection to PCB ground plane or heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD44H11T4, MJD44H11RL offers identical performance in reel format for production use, while STN9360 trades voltage headroom and efficiency for cost and footprint in lower-power 24 V applications - requiring explicit validation of V_CEO margin and thermal budget.

Availability

MJD44H11T4 is available at Aetrix Electronics and suitable for industrial motor control, DC-DC converter design, linear audio amplification, and relay/actuator driver circuits requiring stable component supply and long-term manufacturability.

Supply support for MJD44H11T4 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and power applications since 1987.

MJD44H11T4 belongs to the STPOWER bipolar transistor family, engineered for high-current, low-saturation switching and linear amplification in rugged industrial environments - emphasizing thermal reliability and process consistency.

FAQ

What is the maximum safe operating voltage for MJD44H11T4 in continuous DC operation?

The absolute maximum collector-emitter voltage is 80 V with base open (V_CEO). For reliable long-term operation, ST recommends limiting V_CE to ≤ 60 V under continuous DC conditions to maintain margin against transients and temperature-induced degradation, as confirmed by the sustaining voltage V_CEO(sus) = 60 V at I_C = 30 mA.

Can MJD44H11T4 be used in parallel configurations for higher current handling?

Yes - its positive temperature coefficient of V_CE(sat) promotes current sharing when paralleled with identical units. Designers must match h_FE within ±15%, use individual base resistors, and ensure symmetrical PCB layout and thermal coupling to avoid thermal runaway; derate total current to ≤ 14 A for two devices.

Is a heatsink required for MJD44H11T4 at 8 A continuous current?

A heatsink is strongly recommended. At 8 A and V_CE(sat) = 1 V, power dissipation reaches 8 W. With R_thJC = 6.25 °C/W and typical R_thCA > 40 °C/W on standard FR4, junction temperature exceeds 150°C without heatsinking; a 10 °C/W heatsink keeps T_J < 120°C at 25°C ambient.

Does MJD44H11T4 support pulse-width modulation at frequencies above 50 kHz?

Yes - its fast switching speed and SOA compliance (Figure 1) support clean turn-on/turn-off at 100 kHz with appropriate base drive. Measured switching times are <1 µs, but layout inductance and base drive strength must be optimized to avoid overshoot or oscillation in high-dI/dt conditions.