ST9045C

Overview

The ST9045C is a common source N-channel enhancement-mode lateral field-effect RF power transistor designed for broadband commercial and industrial applications at frequencies up to 1.5 GHz. It operates in common source mode at 28 V, delivering high gain and broadband performance. Key electrical parameters include a drain-source voltage of 90 V, continuous drain current of 9 A, and power dissipation of 130 W at 70 °C case temperature. At 945 MHz with VDD = 28 V and IDQ = 300 mA, it achieves an output power of 63 W with 18.5 dB gain and 70% efficiency. The device features excellent thermal stability and is housed in an M243 epoxy-sealed package.

Feature Summary

• Common source configuration optimized for high gain and broadband performance
• Excellent thermal stability suitable for demanding environments
• BeO free package compliant with European Directive 2002/95/EC

Applications

• Broadband commercial applications
• Industrial applications
• Base station amplifiers requiring high linearity

Procurement Notes

Verify the specific revision level (DS11524 Rev 3) against the latest manufacturer documentation before finalizing designs. Confirm that the M243 package dimensions and pinout match the intended PCB layout requirements. Ensure thermal management solutions account for the specified junction-to-case thermal resistance of 1.0 °C/W to maintain safe operating temperatures under maximum load conditions.

Selection Notes

Select this component for designs requiring high output power and gain in the HF band up to 1.5 GHz. Consider the 28 V operating voltage and 9 A current capability when designing power supply rails. Evaluate the impedance data provided for input and drain matching networks at the target frequency to ensure optimal performance and stability within the circuit design.

Part Context

The ST9045C belongs to the family of RF Power LDMOS transistors from STMicroelectronics. It is specifically engineered for high-frequency applications where linear amplification and robust thermal performance are critical. The device serves as a key active component in radio frequency power stages for communication infrastructure.

Replacement Considerations

No public confirmed substitute part numbers are available in the official documentation.

FAQ

What is the maximum operating junction temperature?

The maximum operating junction temperature is 200 °C.

Does the package contain Beryllium Oxide?

No, the ST9045C uses a BeO free package.

What is the typical gain at 945 MHz?

The typical gain is 18.5 dB at 945 MHz with VDD = 28 V and IDQ = 300 mA.