onsemi NJD2873

Overview

NJD2873 from onsemi is an NPN silicon power transistor in DPAK (TO-252) surface-mount package, designed for high-gain audio amplifier stages. It delivers 2 A continuous collector current, 50 V V_CEO, and 15 W total device dissipation at T_C = 25°C, with h_FE ≥ 120 @ I_C = 500 mA and f_T ≥ 65 MHz - enabling robust low-distortion audio output drive.

For engineers reviewing the NJD2873 datasheet, pinout, applications, or equivalent options, key selection criteria include verified DC current gain across temperature, low V_CE(sat) under 1 A load, thermal resistance R_JC = 10 °C/W, Pb-free compliance, and DPAK footprint compatibility with high-power audio PCB layouts.

Technical Context

This NPN bipolar junction transistor operates in linear amplification mode with specified h_FE minima of 120 at 500 mA and 40 at 2 A, supporting stable biasing in Class AB audio output stages. Its f_T ≥ 65 MHz ensures adequate bandwidth for full-range audio signal fidelity without high-frequency roll-off.

V_CE(sat) ≤ 0.3 V at I_C = 1 A / I_B = 0.05 A confirms efficient conduction with minimal voltage drop and heat generation. The device's rated junction temperature range (−65°C to +175°C) and UL 94 V-0 epoxy enable reliable operation in thermally demanding consumer and industrial audio enclosures.

Key Specifications

Pinout & Package

Package: DPAK (TO-252), Case 369C-01, surface-mount with exposed drain pad (pin 2 & 4 tied to collector). Dimensions per ON Semiconductor drawing: 6.20 mm × 6.17 mm × 2.58 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with NJD2873, MJD2873T4G offers identical performance in a different reel configuration, while 2SC5200(O) provides higher voltage capability at the cost of surface-mount compatibility and reduced DC gain - making NJD2873 optimal for compact, high-efficiency DPAK-based audio output stages.

Availability

NJD2873 is available at Aetrix Electronics and suitable for home audio amplifiers, automotive audio output stages, and industrial PA systems requiring stable component supply, Pb-free compliance, and proven thermal performance in DPAK format.

Supply support for NJD2873 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 electronics, with leadership in power management, analog, and discrete devices.

The NJD2873 belongs to onsemi's high-reliability silicon power transistor family, engineered specifically for linear audio amplifier output stages where gain stability, low saturation voltage, and thermal robustness are critical.

FAQ

What is the maximum continuous collector current rating for NJD2873?

The NJD2873 has a maximum continuous collector current (I_C) rating of 2 A at T_C = 25°C. This rating assumes proper heatsinking to maintain case temperature; derating applies above 25°C at 0.1 W/°C. Peak current capability is 3 A for short-duration pulses, as defined in the Absolute Maximum Ratings table of the NJD2873 datasheet.

Does NJD2873 support Pb-free soldering processes?

Yes, the NJD2873T4G variant is explicitly designated as Pb-free and complies with RoHS Directive 2011/65/EU. Its DPAK package is qualified for standard lead-free reflow profiles per JEDEC J-STD-020, including peak temperatures up to 260°C. The "G" suffix in NJD2873T4G confirms Pb-free construction and marking.

What is the typical DC current gain (h_FE) of NJD2873 at 2 A collector current?

The NJD2873 guarantees h_FE ≥ 40 at I_C = 2 A, V_CE = 2 V, and T_C = 25°C. At lower currents (e.g., 500 mA), h_FE rises to ≥ 120. This wide h_FE range supports flexible bias design across operating points, and the device maintains h_FE ≥ 80 over −40°C to +150°C at I_C = 0.75 A, per Electrical Characteristics table.

Can NJD2873 be used in complementary pair configurations?

Yes, NJD2873 is routinely paired with its complementary PNP counterpart, NJD2872, in Class AB push-pull audio output stages. Both share matched thermal characteristics, package type (DPAK), and gain profiles - enabling symmetrical drive, minimized crossover distortion, and balanced thermal loading in dual-rail amplifier designs.

What is the thermal resistance from junction to case (R_JC) for NJD2873?

The NJD2873 has a maximum junction-to-case thermal resistance (R_JC) of 10 °C/W, measured under standard test conditions with the device mounted on a minimum recommended copper pad. This value enables effective heat transfer from the silicon die to an external heatsink or PCB copper plane, supporting continuous operation at up to 15 W dissipation when T_C is held at 25°C.