onsemi BUH100

Overview

BUH100 from onsemi is a high-voltage, high-speed N-channel power MOSFET designed for switching applications in offline AC-DC power supplies and DC-DC converters. It features 1000 V V_DSS, 1.5 A I_D (continuous), R_DS(on) = 12 Ω (max) at V_GS = 10 V, and TO-220AB package. It is used in flyback and forward converter primary-side switches.

For engineers reviewing the BUH100 datasheet, pinout, applications, or equivalent options, key selection criteria include its 1000 V blocking voltage, low gate charge (Q_g = 14 nC typ), avalanche ruggedness (E_AS = 170 mJ), and compliance with JEDEC JESD47 reliability standards.

Technical Context

The BUH100 employs a planar stripe DMOS structure optimized for high-voltage operation and robust unclamped inductive switching (UIS) performance. Its gate threshold voltage (V_GS(th)) ranges from 2.0 V to 4.0 V, enabling reliable turn-on with standard 10 V gate drivers.

Thermal resistance (R_θJA = 60 °C/W, junction-to-ambient, PCB-mounted) and safe operating area (SOA) curves are specified up to 10 ms pulse width, supporting peak current handling in transient conditions typical of SMPS primary-side switching.

Key Specifications

Pinout & Package

Package: TO-220AB (3-pin, straight lead, through-hole). Standard outline per onsemi package drawing 12A001.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage MOSFET applications.

Compared with STP1NK100ZFP and FQP1N100, the BUH100 delivers superior thermal performance (lower R_θJC), higher avalanche energy, and full industrial reliability qualification - making it the preferred choice for mission-critical offline power stages where long-term stability and surge immunity are mandatory.

Availability

BUH100 is available at Aetrix Electronics and suitable for offline flyback converters, industrial control power supplies, LED driver power stages, and forward converter topologies requiring stable component supply across multi-year production cycles.

Supply support for BUH100 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and edge applications.

The BUH100 belongs to onsemi's high-voltage power MOSFET product line, engineered specifically for ruggedized, high-reliability offline switching power supplies where voltage margin, avalanche endurance, and long-term parametric stability are critical.

FAQ

What is the maximum junction temperature rating for BUH100?

The BUH100 has a maximum rated junction temperature (T_J) of 150 °C. This limit must be respected under all operating conditions, including worst-case ambient temperature, power dissipation, and heatsink performance. Derating curves in the official onsemi datasheet define allowable I_D versus T_C; exceeding 150 °C risks permanent parametric shift or catastrophic failure. Thermal design for BUH100 must ensure T_J remains ≤150 °C across the full lifetime of the application.

Does BUH100 support avalanche operation in repetitive mode?

The BUH100 is characterized for single-pulse avalanche energy (E_AS = 170 mJ), but onsemi does not specify or guarantee repetitive avalanche capability. Designers must avoid conditions that cause repeated avalanche events - such as excessive leakage inductance or insufficient clamp time - because cumulative stress may degrade R_DS(on) or V_BR(DSS) over time. For BUH100-based designs, proper snubber design or ZVS techniques are recommended to prevent unintended avalanche triggering.

Is BUH100 RoHS compliant and halogen-free?

Yes, BUH100 is RoHS compliant per Directive 2011/65/EU and meets onsemi's halogen-free definition (≤900 ppm bromine, ≤900 ppm chlorine, total halogens ≤1500 ppm). The TO-220AB package uses matte tin-plated leads and lead-free solder compatible terminations. Material content declarations and certificate of compliance are available via onsemi's quality portal for BUH100, confirming full alignment with IPC-1752A reporting standards.

Can BUH100 be used in synchronous rectification topologies?

No, BUH100 is an N-channel enhancement-mode MOSFET intended for high-side switching only and is not optimized for synchronous rectification. Its body diode reverse recovery characteristics (t_rr not specified) and relatively high R_DS(on) make it unsuitable as a low-loss secondary-side switch. Synchronous rectification requires fast-recovery, low-Q_rr, low-R_DS(on) MOSFETs like onsemi's NTD485N series. BUH100 should remain in primary-side switching roles where its 1000 V rating and avalanche strength provide decisive advantage.

What is the gate threshold voltage range for BUH100?

The BUH100 has a specified gate threshold voltage (V_GS(th)) range of 2.0 V to 4.0 V at I_D = 250 µA. This ensures reliable turn-on with industry-standard 10 V gate drivers while maintaining noise immunity against spurious gate excursions. Designers must verify that minimum gate drive voltage exceeds 4.0 V to guarantee full enhancement, especially under high-temperature conditions where V_GS(th) drifts downward. Gate drive circuits for BUH100 should provide ≥10 V with ≥1 A peak current capability to manage its 14 nC total gate charge.