STMicroelectronics PD55035-E

Overview

PD55035-E from STMicroelectronics is an N-channel enhancement-mode lateral MOSFET RF power transistor in PowerSO-10RF (formed lead) package, designed for common-source broadband amplification up to 1 GHz. It delivers 35 W output power at 500 MHz with 16.9 dB gain and 62% drain efficiency under 12.5 V supply, targeting mobile radio transmitters requiring high linearity and thermal stability.

For engineers reviewing the PD55035-E datasheet, PD55035-E pinout, PD55035-E application, or PD55035-E equivalent, key selection criteria include its 40 V drain-source breakdown voltage, 1.0 °C/W junction-to-case thermal resistance, 95 W power dissipation at 70°C case temperature, and verified load mismatch tolerance up to 20:1 VSWR - critical for rugged RF front-end design.

Technical Context

This device implements ST's LDMOS technology in a true SMD plastic RF power package, optimized for high-frequency operation in common-source configuration. Its lateral structure enables excellent thermal stability and superior linearity over wide bandwidths, validated by s-parameter data up to 1500 MHz across multiple bias conditions (IDQ = 200 mA to 3 A).

The PowerSO-10RF package features JEDEC-approved mechanical dimensions, integrated heat slug for direct PCB thermal coupling, and gull-wing leads enabling automated assembly. Mounting guidelines are specified in ST application note AN1294, addressing RF grounding, thermal vias, and microstrip impedance control for 50 Ω systems.

Key Specifications

Pinout & Package

PD55035-E uses the PowerSO-10RF (formed lead) package - a JEDEC-approved, high-power SMD RF package with exposed drain pad for thermal conduction and three dedicated terminals: Gate, Source, and Drain. The package integrates a metal heat slug on the underside, requiring solder paste stencil optimization and thermal via array under the drain area per AN1294.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MRF101AN and PD57003-E, PD55035-E offers the best balance of 35 W output, 16.9 dB gain, and SMD manufacturability specifically for VHF/UHF mobile radio - where thermal density, board space, and ruggedness under antenna mismatch are primary design drivers.

Availability

PD55035-E is available at Aetrix Electronics and suitable for mobile radio transmitters, land mobile base stations, and amateur radio amplifiers requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for PD55035-E 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, specializing in automotive, industrial, and power discrete solutions with strong RF and analog design heritage.

PD55035-E belongs to ST's LdmoST plastic family of RF power transistors, engineered for high-gain, broadband commercial and industrial amplification - particularly where SMD manufacturability, thermal robustness, and linearity in mobile radio applications are essential.

FAQ

What is the maximum safe operating frequency for PD55035-E?

PD55035-E is characterized and guaranteed for operation up to 1 GHz, with published s-parameters and performance curves extending to 1500 MHz. At 1 GHz, it delivers usable gain (>7 dB) and efficiency (>40%) under 12.5 V/2 A bias, though output power drops to ~15 W. Operation beyond 1 GHz is not recommended without full system-level validation.

Can PD55035-E replace PD55035S-E in existing designs?

Yes - PD55035-E (formed lead) and PD55035S-E (straight lead) share identical die, electrical specs, and thermal performance. The only difference is lead form: gull-wing vs. straight. PCB footprint and soldering process must match the selected variant; reflow profiles and stencil design differ slightly due to lead geometry and standoff height (A1 = 0–0.1 mm vs. 1.62–1.72 mm).

How does the PowerSO-10RF package compare thermally to traditional flange-mount packages?

PowerSO-10RF achieves RthJC = 1.0 °C/W - comparable to many flange-mount packages - by integrating a large exposed drain pad that transfers heat directly to the PCB. Unlike flange-mount devices, it eliminates mechanical mounting hardware and enables double-sided cooling, but requires strict adherence to AN1294 layout rules (e.g., ≥12 thermal vias, 0.3 mm diameter, filled with solder).

Is PD55035-E suitable for pulsed RF applications?

Yes - its 40 V V(BR)DSS, 7 A ID rating, and 165°C TJ(max) support pulsed operation with peak drain voltages up to 35 V and duty cycles ≤20%. Published test data includes 175 MHz and 500 MHz pulsed performance (Figures 16–20); derating guidance for pulse width and repetition rate is provided in Section 1.1 of the datasheet.