onsemi MJD148T4

Overview

MJD148T4 from onsemi is an NPN silicon power transistor in DPAK (TO-252) surface-mount package, rated for 45 V_CEO, 4.0 A continuous collector current, and 20 W power dissipation at T_C = 25°C. It delivers low V_CE(sat) of 0.5 V at I_C = 2 A / I_B = 0.2 A and DC current gain (h_FE) up to 375, making it suitable for low-speed switching and linear amplification in automotive power supplies and industrial motor drivers.

For engineers reviewing the MJD148T4 datasheet, pinout, applications, or equivalent options, key selection criteria include its AEC-Q101 qualification, thermal resistance R_θJC = 6.25°C/W, safe operating area (SOA) limits at T_J(pk) = 150°C, and Pb-free RoHS-compliant DPAK-3 package with dual collector terminals.

Technical Context

This NPN bipolar junction transistor operates in linear and saturated switching modes with verified h_FE minima of 40 (I_C = 10 mA), 50 (I_C = 0.5 A), and 30 (I_C = 3 A) at V_CE = 1 V. Its f_T = 3 MHz at I_C = 250 mA confirms suitability for audio-frequency amplification and PWM-driven relay/motor control.

The device features dual collector pins (pins 2 and 4) sharing internal connection, enabling higher current handling and improved thermal spreading across the DPAK copper tab. Its ESD rating meets HBM Class 3B (≥8 kV) and is qualified per AEC-Q101 for automotive underhood applications requiring robustness against thermal cycling and vibration.

Key Specifications

Pinout & Package

DPAK-3 (Case 369C, Style 1) surface-mount package with exposed copper thermal pad (pin 2/4 collector connection), 6.10 × 6.54 × 2.28 mm footprint, and 2.29 mm lead pitch. Pin 1 is base, pin 2 and pin 4 are internally connected collectors, pin 3 is emitter.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD148T4, MJD122T4G offers higher voltage headroom but reduced gain linearity at mid-current, while STN9360 trades surface-mount compatibility and automotive qualification for lower thermal resistance and through-hole ease-of-use.

Availability

MJD148T4 is available at Aetrix Electronics and suitable for automotive lighting control, industrial relay drivers, and DC motor speed control requiring stable component supply, long-term lifecycle support, and AEC-Q101-compliant sourcing.

Supply support for MJD148T4 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 energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The MJD148T4 belongs to onsemi's general-purpose NPN power transistor family designed for cost-sensitive, thermally constrained applications requiring AEC-Q101 reliability and DPAK-level integration in automotive body electronics and industrial controls.

FAQ

What is the maximum continuous collector current rating for MJD148T4?

The MJD148T4 is rated for 4.0 A continuous collector current at case temperature T_C = 25°C. Derating applies above 25°C at 0.16 W/°C, limiting usable current in high-temperature environments unless heatsinking is implemented. This rating assumes proper PCB copper area per onsemi's recommended minimum pad sizes.

Does MJD148T4 support automotive-grade reliability requirements?

Yes, MJD148T4 is AEC-Q101 qualified and PPAP capable, with NJV prefix variants (e.g., NJVMJD148T4G) designated for automotive applications requiring unique site and control change tracking. It meets HBM ESD Class 3B (≥8 kV) and operates across −55°C to +150°C junction temperature range.

How are pins 2 and 4 used in the MJD148T4 DPAK package?

Pins 2 and 4 of the MJD148T4 are internally connected collector terminals. They must be soldered to the same net on the PCB-typically a large copper pour or thermal pad-to maximize current capacity and thermal dissipation. Using only one collector pin violates SOA limits and risks premature failure.

What is the typical DC current gain (h_FE) of MJD148T4 at 2 A collector current?

At I_C = 2 A, V_CE = 1 V, and T_C = 25°C, the MJD148T4 guarantees h_FE ≥ 30 (minimum) with typical values reaching 100–150. This gain level supports reliable saturation with base drive currents ≥200 mA, ensuring low V_CE(sat) in switching applications.

Can MJD148T4 replace older through-hole transistors like TIP31C in new designs?

MJD148T4 is not a direct replacement for TIP31C due to different package (DPAK vs. TO-220), pinout, and thermal characteristics. While both are NPN power transistors, MJD148T4 requires surface-mount layout and thermal pad design; its 45 V rating also differs from TIP31C's 100 V. Redesign is necessary for migration.