Power Transistor AD143 PNP, TO-3

Power Transistor AD143 PNP, TO-3

Transistors

Reference: TRAD143

Part.No: AD143

€5.50

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The AD143 is a classic PNP Germanium Power Transistor in a TO-3 package. Designed for high-power audio amplifier output stages and other demanding applications requiring robust switching and amplification at moderate to high current levels.

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Description
Product Details

AD143 Germanium Power Transistor - Vintage Audio Amplifier Output Stage

The AD143 is a robust PNP germanium power transistor housed in a TO-3 package, renowned for its use in vintage and contemporary audio amplifier output stages. Its ability to handle substantial collector currents and its characteristic germanium warmth make it a preferred choice for audio enthusiasts and professional audio designers seeking reliable power amplification.

Functions & Applications

Germanium Junction: Classic PNP germanium construction delivers smooth, warm nonlinearity prized in audio applications.
TO-3 Heavy-Duty Package: Direct mounting to large heatsinks via M3 stud; built-in mechanical robustness for high-power circuits.
High Current Capability: Suitable for driving speakers and other power loads directly from amplifier output stages.
Complementary to AD144: Forms a complementary BJT pair with the NPN AD144 for push-pull amplifier designs.

Technical Specifications

Parameter	Value / Specification
Transistor Type	BJT (Bipolar Junction Transistor)
Polarity / Channel	PNP
Package / Case	TO-3
Transistor Type	PNP Germanium BJT
Package	TO-3
Mounting Type	Stud Mount (M3), Requires Mica Insulator

Frequently Asked Questions

Q: Do I need a mica insulator when mounting the AD143 on a heatsink?
A: Yes. The TO-3 case is internally connected to the Collector terminal. Always place a mica insulator (with thermal grease on both sides) between the transistor case and the heatsink to prevent electrical short circuit while maintaining thermal contact.

Q: What is the complementary NPN transistor to pair with the AD143?
A: The AD144 is the complementary NPN transistor. Together, AD143 and AD144 form a matched pair ideal for push-pull audio amplifier output stages.

Notes

Vintage germanium power transistor. May be NOS (new old stock) or reclaimed; performance characteristics are consistent with published datasheets for this classic audio part. Ensure proper thermal management and mica insulation when mounting.

Note: Price refers to one (1) piece. The component is shipped in bulk without individual packaging.

Transistor Type: BJT (Bipolar Junction Transistor)
Transistor Polarity / Channel: PNP
Transistor Case Style: TO-3

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