UNR921LJ0L

Overview

The UNR921LJ0L is a Silicon NPN epitaxial planar transistor with built-in resistors, designed for digital circuits. It features an SS-Mini3-F1 package (EIAJ SC-89) and supports automatic insertion via tape packing. Key electrical parameters include a collector-emitter voltage of 50 V, a collector current of 100 mA, and a total power dissipation of 125 mW. The device incorporates two internal bias resistors: R1 is 4.7 kΩ and R2 is 4.7 kΩ. The forward current transfer ratio (hFE) ranges from 20 to 400 at IC = 5 mA and VCE = 10 V. The transition frequency is 150 MHz.

Feature Summary

• Integrates dual bias resistors within a single compact package to reduce component count and equipment size.
• Utilizes an SS-Mini type surface-mount package compatible with automatic insertion processes.
• Optimized for digital circuit applications with standardized resistance values.

Applications

• Digital logic interface circuits
• Switching applications in general electronic equipment
• Automated assembly lines requiring tape-packed components

Procurement Notes

Verify the specific ordering suffix against the manufacturer's latest documentation to confirm availability and exact pin configuration. Confirm that the SS-Mini3-F1 package dimensions match the target PCB footprint. Ensure compliance with RoHS standards if required by the end application. Check for any obsolescence notices or lifecycle status updates directly from Panasonic Industry.

Selection Notes

Select this component when a pre-biased NPN transistor with equal base and emitter resistor values is required. The 4.7 kΩ internal resistors simplify drive circuit design for standard logic levels. Consider the 125 mW power dissipation limit and thermal derating curves for high-temperature environments. Verify that the 50 V voltage rating meets the maximum operating conditions of the target circuit.

Part Context

This part belongs to the UNR921xJ Series, which includes various combinations of internal bias resistors. The 'L' designation specifically indicates the 4.7 kΩ / 4.7 kΩ resistor configuration. Other series members offer different resistance ratios for varied switching speeds and drive requirements. All parts share the same physical package and basic electrical ratings.

Replacement Considerations

Direct substitutes must match the 50V/100mA rating, SS-Mini3-F1 package, and 4.7kΩ/4.7kΩ internal resistance values. Verify hFE and fT specifications to ensure equivalent switching performance. Cross-reference with other manufacturers' pre-biased transistor offerings using identical pinout and resistance configurations.

FAQ

What are the specific values of the internal bias resistors in the UNR921LJ?

The UNR921LJ contains two internal resistors: R1 (Base resistor) is 4.7 kΩ and R2 (Emitter resistor) is 4.7 kΩ.

What is the maximum collector current for this device?

The absolute maximum rating for the collector current (IC) is 100 mA at an ambient temperature of 25°C.

Is this transistor suitable for high-frequency switching applications?

Yes, it has a transition frequency (fT) of 150 MHz, making it suitable for many digital switching applications.