BC637

Single Bipolar Transistors Overview

The onsemi BC637 is an NPN epitaxial silicon transistor housed in a TO-92 package. It supports a collector current of 1 A and peak currents up to 1.5 A. The device features a collector-emitter breakdown voltage (BVCEO) of 60 V and a collector-base voltage of 60 V. Power dissipation reaches 1 W at 25°C ambient temperature. The transition frequency is rated at 100 MHz, with a minimum DC current gain of 40 at 150 mA collector current.

Single Bipolar Transistors Feature Summary

• NPN epitaxial silicon construction for switching and amplifier applications
• Complements the BC638 PNP transistor within the same series
• Capable of handling high continuous collector currents

Single Bipolar Transistors Applications

• General-purpose switching circuits
• Linear amplifier stages
• Driver circuits requiring medium power output

Single Bipolar Transistors Procurement Notes

Verify the specific manufacturer source, as the BC637 designation appears across multiple vendors including Fairchild and onsemi. Confirm RoHS compliance status and lead times directly with suppliers. Ensure the ordering suffix matches the required packaging format. Check for any recent product discontinuance notices or lifecycle changes before finalizing procurement plans.

Single Bipolar Transistors Selection Notes

Select this component when a 60 V collector-emitter rating is required, distinguishing it from the 45 V BC635 variant. It offers higher voltage tolerance than the BC635 while maintaining similar current capabilities. Consider the complementary BC638 if a matched PNP pair is needed for push-pull configurations.

Single Bipolar Transistors Part Context

The BC637 belongs to a family of NPN medium power transistors that includes the BC635 and BC639. These devices share identical physical packages and thermal characteristics but differ primarily in their voltage ratings. This specific model provides a middle-ground voltage specification between the lower-rated BC635 and the higher-rated BC639.

Single Bipolar Transistors Replacement Considerations

The BC635 serves as a direct pin-compatible substitute if the application voltage does not exceed 45 V. Conversely, the BC639 can replace this part where higher voltage ratings are beneficial. Verify that the replacement maintains the required 1 A current capability and TO-92 footprint.