STMicroelectronics PD55025

Overview

PD55025 from STMicroelectronics is a common-source, N-channel enhancement-mode lateral MOSFET RF power transistor in PowerSO-10RF package. It delivers 25 W output power with 14.5 dB gain at 500 MHz and 12.5 V supply, featuring 1.2 °C/W junction-to-case thermal resistance and 40 V drain-source breakdown voltage. Designed for car mobile radio amplifiers, it operates up to 1 GHz in broadband industrial and commercial RF power stages.

For engineers reviewing the PD55025 datasheet, PD55025 pinout, PD55025 application, or PD55025 equivalent, this page provides verified electrical specifications, thermal performance data, impedance matching guidance at 175–1000 MHz, and real-world biasing behavior across V_GS, I_DQ, and V_DD variations - critical for RF PA design validation and thermal management planning.

Technical Context

This LDMOS device uses lateral structure for high thermal stability and linearity in common-source configuration. Its gate threshold voltage (2.0–5.0 V) and low on-resistance (0.7–0.8 V at I_D = 3 A) enable stable Class AB operation under 12–13.8 V supply rails.

Input/output impedance varies significantly with frequency: at 500 MHz, Z_IN = 0.93 − j1.53 Ω and Z_DL = 1.12 + j0.20 Ω; S-parameters confirm strong forward gain (|S₂₁| = 0.78 @ 500 MHz, V_DS = 12.5 V, I_D = 500 mA) and excellent input return loss (−17.8 dB).

Key Specifications

Pinout & Package

PD55025 is housed in PowerSO-10RF plastic package - ST's first JEDEC-approved high-power SMD RF package, available in straight-lead (PD55025S) and formed-lead (gull-wing) variants. Dimensions include E = 15.4 mm (straight), E = 14.1 mm (formed), D = 9.5 mm, and thermal pad optimized for PCB copper pour attachment.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RF power transistor applications.

Compared with MRF158 and PD57003, PD55025 offers optimal balance of gain, efficiency, and thermal robustness at 12.5 V operation - making it ideal for cost-sensitive mobile radio designs where 25 W output suffices and board space limits multi-stage architectures.

Availability

PD55025 is available at Aetrix Electronics and suitable for car mobile radio amplifiers, UHF land mobile radio base stations, ISM band industrial heater drivers, and amateur radio HF/VHF linear amplifiers requiring stable component supply across extended production cycles.

Supply support for PD55025 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and RF devices for industrial, automotive, and consumer markets.

PD55025 belongs to ST's LdmoST Plastic family of lateral RF power MOSFETs, engineered specifically for high-linearity, broadband RF amplification in space-constrained SMD applications - especially mobile and portable radio systems.

FAQ

What is the maximum safe operating frequency for PD55025?

PD55025 is characterized and guaranteed up to 1 GHz, with published S-parameters, gain, and efficiency data at 175 MHz, 480–520 MHz, and 1000 MHz. At 1 GHz, |S₂₁| = 0.23 dB and P_OUT drops to ~5 W under standard bias - confirming functional operation but reduced output capability.

Can PD55025 operate from a 13.8 V supply?

Yes - absolute maximum V_(BR)DSS is 40 V, and test data shows P_OUT increases to ~27 W at 13.8 V with identical 200 mA I_DQ. Drain efficiency improves slightly, but thermal dissipation rises; heatsink design must accommodate increased P_DISS at same output power.

Is PD55025 pin-compatible with PD55025S?

Yes - both share identical PowerSO-10RF footprint and pin assignment (GATE-SOURCE-DRAIN). PD55025 uses formed leads (gull-wing), PD55025S uses straight leads; PCB land pattern is identical, but reflow profile differs due to leadform geometry.

What thermal interface material is recommended for PD55025?

ST recommends soldering the exposed thermal pad directly to a minimum 25 mm² copper pour on the PCB, with ≥2 oz copper thickness. No thermal paste or tape is required - the PowerSO-10RF package is designed for direct metal-to-metal conduction, achieving the specified 1.2 °C/W R_th(j-c) when properly mounted.