BD434S

Overview

The BD434S is a PNP silicon epitaxial-base power transistor manufactured by onsemi. It is designed for medium-power linear and switching applications, serving as the complementary device to NPN types such as the BD433. The component features a maximum collector current of 4 A and a collector-emitter voltage rating of 22 V. It utilizes a TO-126 flange-mount package with through-hole terminals. The device exhibits a minimum DC current gain (hFE) of 50 and a transition frequency (fT) of 3 MHz.

Feature Summary

• Complementary PNP configuration paired with NPN power transistors
• Suitable for medium-power linear and switching operations
• Flange-mount plastic package for thermal management

Applications

• Car-radio output stages
• Medium-power linear amplifier circuits
• General-purpose switching applications

Procurement Notes

Verify the specific suffix 'S' against official datasheets to confirm package variations or compliance updates. Confirm RoHS status via Material Composition Declaration documents. Check lifecycle status as related complementary devices may be obsolete. Ensure lead availability aligns with project timelines given potential discontinuation of legacy series.

Selection Notes

Select this component when a PNP counterpart to the BD433 NPN transistor is required. Evaluate the 22 V collector-emitter voltage limit against circuit requirements. Consider the TO-126 package for mounting constraints. Verify that the 4 A current rating meets load demands. Assess thermal performance needs for linear operation modes.

Part Context

The BD434 belongs to a family of complementary silicon power transistors including BD433, BD435, and BD437 (NPN) and BD434, BD436, and BD438 (PNP). These devices are housed in Jedec SOT-32 plastic packages. The series is engineered for robust performance in automotive audio and general power control environments.

Replacement Considerations

Public confirmed substitute part numbers were not identified in the provided documentation.