BD242 PNP Transistor Pinout Datasheet

Introduction

The BD242 is a PNP epitaxial-base power transistor designed for medium power switching and linear amplification applications. It belongs to the BD241/BD242 complementary transistor family, where BD242 serves as the PNP counterpart to BD241. With multiple variants (BD242, BD242A, BD242B, BD242C) offering varying voltage ratings, this transistor affords flexibility to designers working with different supply ranges.

Packaged in the TO-220 (plastic) housing, BD242 offers good thermal dissipation when mounted on a heatsink, making it suitable for moderate power circuits. Its planar epitaxial design ensures stable current gain and acceptable saturation voltage, which aids performance in amplifier output stages, driver circuits, and switching stages where a PNP device is needed.

BD242 PNP Transistor

The transistor sees frequent use in complementary amplifier designs (paired with BD241) in audio output stages, push-pull layouts, regulator circuits, and power switching segments. Its specification margin allows it to be used in circuits where negative side conduction or PNP stage is required, giving designers symmetrical operation alongside NPN devices.

Pinout of BD242

Key Features

• PNP polarity suited for high-side or complementary amplifier stages
• Multiple voltage variants (standard, A, B, C) for design flexibility
• Good linear behavior and stable gain in power region
• Low saturation levels under heavy conduction
• Package conducive to effective thermal management
• Designed for complementary pairing with BD241

Specifications/Characteristics

• Collector-Emitter Voltage, VCEO = –45 V for BD242 (higher in variants: –60 V, –80 V, –100 V)
• Collector-Emitter With Base Open (Sustaining), VCE(sus) = –45 V for BD242 (higher for variants: –60 / –80 / –100 V)
• Collector-Base Voltage, VCBO = –55 V (BD242), increasing in variants (–70 / –90 / –115 V)
• Emitter-Base Breakdown Voltage, VEBO = –5 V
• Collector Current, Continuous IC = –3 A
• Collector Current (Pulse), ICM = –5 A
• Base Current, IB = –1 A (absolute maximum)
• Collector Power Dissipation, PC = 40 W (TC = 25 °C)
• Junction Temperature, Tj = 150 °C
• Storage Temperature Range, Tstg = –65 to +150 °C
• DC Current Gain, hFE = 25 (IC = –1 A, VCE = –4 V)
• DC Current Gain, hFE = 10 (IC = –3 A, VCE = –4 V)
• Collector-Emitter Saturation Voltage, VCE(sat) = –1.2 V (IC = –3 A, IB = –0.6 A)
• Base-Emitter On Voltage, VBE(on) = –1.8 V (IC = –3 A, VCE = –4 V)
• Thermal Resistance, Junction-to-Case, θJC ≈ 3.12 °C/W

Pin Configuration

Comparison of BD240 vs BD242 vs BD244 (PNP)

• BD240 is the lower-voltage PNP in the family, rated around –45 V collector-emitter, suited for moderate-voltage PNP applications where full headroom is not needed.
• BD242 offers a step up in voltage flexibility, with variants spanning –45 V to –100 V, allowing designers to select the version best suited to their supply voltage while keeping current capability intact.
• BD244 is the higher-voltage PNP option in the series; it supports more demanding voltage environments and is used when higher voltage tolerance is required in amplifier or switching circuits.
• All three share the same continuous current rating (–3 A), power dissipation (40 W), and similar gain and saturation behavior. Their differences lie primarily in how much voltage headroom they provide while maintaining matched performance in current, gain, and switching.

More Circuit Layouts

Key Applications of BD242 PNP Transistor

• Complementary amplifier output (paired with BD241)
• Audio driver and output stages
• PNP switching and power regulation circuits
• High-side switching in analog and power supplies
• General-purpose PNP usage in medium power systems

NPN Complimentary Transistor

• The complementary NPN transistor for BD242 is BD241.

Equivalent Transistors of BD242 PNP Transistor

Some possible alternatives or equivalents for BD242 include:

• BD240 (if lower voltage suffices)
• BD244 (if higher voltage is needed)
• Other PNP medium-power transistors with matching current/voltage class in TO-220 form
• Power PNP transistors like TIP32C, MJE2955, or others with similar ratings

(Pin configuration of some transistors mentioned here may different from BD242).

Datasheet of BD242 PNP Transistor

Click the following Button to download the datasheet of BD242 Transistor :

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