BUT12AI,127 Equivalent & Substitute Parts Reference

Part Overview

The BUT12AI,127 from NXP USA Inc. is a bipolar NPN power transistor with a maximum collector-emitter voltage of 450 V, a collector current up to 8 A, and a power dissipation of 110 W, housed in a TO-220AB package. Its key application is in high-voltage, high-current switching where reliability and efficiency are critical. The device is currently designated as obsolete, making the identification of compatible and equivalent transistor models necessary to maintain serviceability, ensure supply continuity, and support design maintenance.

Substiute Parts

BUT12AI,127

NXP USA Inc.In Stock: 989BUT12AI,127 Datasheet

Current PartRFQ

MJE18008G

onsemiIn Stock: 8170MJE18008G Datasheet

DirectRFQ

BUL58D

STMicroelectronicsIn Stock: 34106BUL58D Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute and equivalent bipolar NPN transistors for the BUT12AI,127 are determined strictly by matching critical electrical and mechanical parameters that define device compatibility in this category. These parameters include Transistor Type, Maximum Collector Current (Ic), Collector-Emitter Breakdown Voltage (Vce), Vce Saturation, DC Current Gain (hFE), Maximum Power Dissipation, Operating Temperature, Mounting Type, and Package/Case. Only parts that fit within these parameters are listed as substitutes.

Parameter Comparison

Engineering Selection Recommendations

Selection of substitute transistors for the obsolete BUT12AI,127 is based on matching device specifications and environmental compliance data provided. Both MJE18008G (onsemi) and BUL58D (STMicroelectronics) are listed as RoHS3 compliant and REACH unaffected, which supports ongoing regulatory requirements for electronic assemblies.

Frequently Asked Questions (FAQ)

Q1: Which parameters are critical when substituting the BUT12AI,127 bipolar transistor?
A1: Key parameters include Transistor Type, Maximum Collector Current, Collector-Emitter Breakdown Voltage, Vce Saturation, DC Current Gain (hFE), Maximum Power Dissipation, Operating Temperature, Mounting Type, and Package/Case.

Q2: Are the MJE18008G and BUL58D direct mechanical replacements for the BUT12AI,127?
A2: Yes, all parts share the TO-220-3 package and through-hole mounting, meeting mechanical compatibility requirements.

Q3: How important are compliance certifications such as RoHS and REACH for these substitutes?
A3: RoHS3 compliance and REACH status are essential for use in regulated markets and ensure substitutes meet current environmental and safety standards.

Q4: What should be verified regarding electrical parameters when selecting substitutes?
A4: Electrical compatibility is ensured by matching Current - Collector (Ic), Voltage - Collector Emitter Breakdown, Vce Saturation, and DC Current Gain (hFE) as detailed in the parameter comparison table.

Q5: Is inventory availability a selection factor?
A5: Inventory levels are noted but not a substitution criterion; selection here is strictly electrical, mechanical, and compliance-focused.