FJN3309RTA

Overview

The FJN3309RTA is a digital NPN epitaxial silicon transistor manufactured by Fairchild Semiconductor, now part of onsemi. It features built-in bias resistors configured for a single unit with an input resistance of 47 kOhms and a typical resistor ratio of 2.1. The device supports a collector-emitter voltage (VCEO) of 50 V and a continuous collector current of 100 mA, with a power dissipation rating of 300 mW. Packaged in a TO-92-3 Kinked Lead through-hole format, it operates within a temperature range of -55°C to +150°C and includes a minimum DC current gain (hFE) of 56.

Feature Summary

• Integrates bias resistors directly into the transistor structure to simplify circuit design and reduce component count.
• Utilizes NPN epitaxial silicon technology for reliable switching performance in digital applications.
• Designed for through-hole mounting using a TO-92-3 package with kinked leads for secure board attachment.

Applications

• Switching circuits requiring integrated biasing
• Inverter logic gates
• Interface circuits between logic families
• Driver circuits for low-power loads

Procurement Notes

Verify availability status as this component may be discontinued or subject to supply constraints. Confirm RoHS compliance details via official datasheets before integration. Ensure ordering suffixes match required packaging formats such as ammo packs. Cross-reference manufacturer part numbers to distinguish between legacy Fairchild and current onsemi production runs.

Selection Notes

Select this component when a single NPN digital transistor with specific 47 kOhm input resistance is required. Verify that the 50 V collector-emitter voltage and 100 mA current limits meet circuit demands. Consider the TO-92-3 package dimensions for PCB layout compatibility. Check thermal dissipation requirements against the 300 mW power rating under operating conditions.

Part Context

This part belongs to the FJN series of Bias Resistor Built-In transistors originally developed by Fairchild Semiconductor. These devices combine NPN transistors with internal resistors to replace multiple discrete components. The series offers complementary PNP options and various resistor ratios to accommodate different logic interface needs across consumer and industrial electronics.

Replacement Considerations

Check for direct equivalents from onsemi or other manufacturers offering identical pinouts and electrical characteristics. Verify that substitute parts maintain the same 47 kOhm input resistance and TO-92-3 package form factor to ensure mechanical compatibility without redesign.