TIP121G

Single Bipolar Transistors Overview

The TIP121G is a monolithic NPN silicon power Darlington transistor manufactured by onsemi in a TO-220AB package. It features a maximum continuous collector current of 5 A and a collector-emitter sustaining voltage of 80 Vdc at 100 mAdc. The device offers a minimum DC current gain (hFE) of 1000 and a maximum collector-emitter saturation voltage of 4.0 Vdc at 5.0 Adc. Total power dissipation reaches 65 W at 25°C case temperature, with an operating junction temperature range from -55°C to +150°C.

Single Bipolar Transistors Feature Summary

• Monolithic construction integrating two transistors with built-in base-emitter shunt resistors for simplified drive requirements.
• High DC current gain performance suitable for general-purpose amplifier and low-speed switching applications.
• Low collector-emitter saturation voltage characteristics to minimize conduction losses during operation.

Single Bipolar Transistors Applications

• General-purpose amplifier circuits
• Low-speed switching applications
• Complementary driver stages

Single Bipolar Transistors Procurement Notes

Verify the specific ordering suffix 'G' indicates a lead-free package configuration as defined in the manufacturer's documentation. Confirm that the TO-220AB mechanical dimensions match the target PCB footprint requirements. Ensure thermal management solutions account for the specified junction-to-case thermal resistance values under expected load conditions.

Single Bipolar Transistors Selection Notes

Select this component when high input impedance and substantial current handling are required without complex biasing networks. The integrated shunt resistors simplify base drive circuitry compared to discrete Darlington pairs. Consider the 80 V collector-emitter voltage rating relative to the maximum supply voltage and transient spikes present in the target application environment.

Single Bipolar Transistors Part Context

This part belongs to the TIP12x complementary silicon transistor family, which includes NPN types (TIP120, TIP121, TIP122) and PNP types (TIP125, TIP126, TIP127). The series is designed for medium-power applications requiring robust current amplification capabilities within standard through-hole packaging formats.

Single Bipolar Transistors Replacement Considerations

TIP121

Single Bipolar Transistors FAQ

What is the function of the internal resistors in the TIP121G?

The device includes built-in base-emitter shunt resistors that help discharge stored charge in the base region, improving turn-off speed and preventing false triggering due to leakage currents.

How does the collector-emitter sustaining voltage differ from the rated voltage?

The collector-emitter sustaining voltage (VCEO(sus)) is the minimum voltage the device can withstand with the base open-circuited, specified at 80 Vdc for the TIP121G, whereas the absolute maximum rating may allow higher transient voltages under pulsed conditions.