onsemi MJE18006

Overview

MJE18006 from onsemi is an NPN bipolar power transistor in TO-220AB package, rated for 1000 V_CES, 6 A continuous collector current, and 100 W dissipation at T_C = 25°C. It delivers high DC current gain (h_FE ≥ 14 at I_C = 0.5 A, T_J = 125°C), fast switching (t_on ≤ 100 ns, t_off ≤ 2.5 µs), and low V_CE(sat) (0.25 V typical at I_C = 1.3 A, I_B = 0.13 A) - engineered specifically for 220 V line-operated switch-mode power supplies and electronic light ballasts.

For engineers reviewing the MJE18006 datasheet, pinout, applications, or equivalent options, key selection considerations include its 450 V_CEO sustaining voltage, tight parametric lot-to-lot consistency, Pb-free RoHS-compliant TO-220AB package, absence of current tail during turn-off, and no requirement for a base coil to ensure clean switching in high-voltage SMPS designs.

Technical Context

This NPN power transistor employs a state-of-the-art die optimized for high-voltage switching applications with minimal base drive requirements. Its flat h_FE curve across temperature (14–34 at I_C = 0.5–3.0 A, T_J = 25–125°C) and low dynamic saturation voltage (V_CE(dsat) ≤ 12 V after 1 s at I_C = 1.3 A, T_J = 125°C) support stable gain control and reduced conduction losses in flyback and resonant converters.

The device features a reverse-biased safe operating area (RBSOA) validated under clamped inductive conditions up to 300 V, with storage time (t_si) ≤ 2.75 µs and crossover time (t_c) ≤ 350 ns at I_C = 3.0 A, T_J = 125°C - enabling reliable operation in electronic ballasts where simultaneous high voltage and current occur during turn-off.

Key Specifications

Pinout & Package

Package: TO-220AB (Case 221A-09), standard through-hole, Pb-free, RoHS-compliant. Mounting tab is collector (electrically connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BU508A and MJE13009, the MJE18006 offers optimal balance of 1000 V ruggedness, TO-220AB compatibility, and sub-3 µs turn-off - making it the preferred choice for cost-sensitive, thermally constrained 220 V AC switch-mode power supplies where layout reuse and thermal efficiency are critical.

Availability

MJE18006 is available at Aetrix Electronics and suitable for switch-mode power supplies, electronic light ballasts, and industrial AC-DC adapters requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MJE18006 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, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MJE18006 belongs to onsemi's high-voltage bipolar power transistor product line, designed specifically for robust, cost-effective switching in 220 V line-operated power conversion systems such as electronic ballasts and offline SMPS.

FAQ

What is the maximum junction temperature for the MJE18006?

The MJE18006 has an operating junction temperature range of −65°C to +150°C. Its thermal resistance R_JC is 1.25°C/W, meaning that at 100 W dissipation and T_C = 25°C, the junction temperature reaches 150°C - the absolute maximum. Derating is required above 25°C case temperature at 0.8 W/°C to maintain reliability. The MJE18006 must be mounted on an appropriately sized heatsink to avoid exceeding this limit during continuous operation.

Is the MJE18006 pin-compatible with other TO-220 NPN transistors like the MJE13005?

No, the MJE18006 is not pin-compatible with the MJE13005. While both use TO-220AB packages, the MJE13005 has emitter-base-collector (E-B-C) pinout, whereas the MJE18006 uses emitter-base-collector (E-B-C) in the same physical order - but its internal die structure and SOA characteristics differ significantly. The MJE18006's optimized switching behavior and clamped RBSOA require verification of drive timing and snubber design even if mechanical fit is identical. Always consult the MJE18006 datasheet before substitution.

Does the MJE18006 require a base turn-off coil in switch-mode applications?

No, the MJE18006 does not require a base turn-off coil. Its "applications specific state-of-the-art die" eliminates current tail during turn-off, enabling clean switching without external coil-based forced commutation. This is confirmed in the official onsemi datasheet (Rev. 7, April 2010), which explicitly states "No Coil Required in Base Circuit for Turn−Off (No Current Tail)" as a core feature of the MJE18006G. This simplifies driver design and improves system reliability in CFL ballasts and SMPS.

What is the safe operating area (SOA) limitation for inductive loads with the MJE18006?

The MJE18006 specifies a reverse-biased safe operating area (RBSOA) verified under clamped conditions up to 300 V, with simultaneous high voltage and current sustained during turn-off. Figure 16 in the datasheet defines limits for inductive switching: at V_CE = 300 V, maximum I_C is ~1.5 A for 10 µs pulses. Exceeding these boundaries risks second breakdown. The MJE18006 must never be operated in unclamped avalanche mode - external clamping (e.g., Zener diode or RCD network) is mandatory for inductive loads.

Can the MJE18006 be used in linear regulator applications?

No, the MJE18006 is not intended for linear regulator use. Its design focuses on switching efficiency - evidenced by fast t_on/t_off, low V_CE(sat), and optimized SOA for pulsed operation - not linear-mode thermal stability. The device lacks guaranteed Safe Operating Area (SOA) curves for DC or long-pulse linear operation. Using the MJE18006 in linear regulation risks thermal runaway due to secondary breakdown, especially above 10 V_CE. For linear applications, select devices explicitly characterized for DC SOA, such as the MJ15003 or similar.