STMicroelectronics PD55035S-E

Overview

PD55035S-E from STMicroelectronics is an N-channel enhancement-mode lateral MOSFET RF power transistor in PowerSO-10RF straight-lead package, designed for common-source broadband amplification up to 1 GHz. It delivers 35 W output power with 16.9 dB gain at 500 MHz under 12.5 V supply and 200 mA quiescent drain current, featuring 1.0 °C/W junction-to-case thermal resistance and 40 V drain-source breakdown voltage - optimized for car mobile radio transmitters.

For engineers reviewing the PD55035S-E datasheet, PD55035S-E pinout, PD55035S-E application, or PD55035S-E equivalent, key selection criteria include RF linearity at 500 MHz, thermal performance under pulsed/continuous operation, SMD-compatible high-power packaging, and load mismatch tolerance (20:1 VSWR capability).

Technical Context

This device operates in common-source configuration with lateral LDMOS architecture, enabling high gain and excellent thermal stability across 175–1500 MHz. Its gate threshold voltage (2.0–5.0 V) and low input capacitance (CISS = 92 pF @ 1 MHz) support stable Class AB biasing and broadband impedance matching.

The PowerSO-10RF straight-lead package integrates a thermally optimized copper leadframe and exposed drain pad, delivering 1.0 °C/W R_thJC and JEDEC-qualified reliability. S-parameter data confirms stable small-signal gain (S21 > 0.87 @ 500 MHz) and input return loss (S11 < –12 dB) across HF to UHF bands.

Key Specifications

Pinout & Package

PD55035S-E uses the PowerSO-10RF straight-lead plastic package - ST's first JEDEC-approved high-power SMD RF package - featuring an exposed drain pad for thermal conduction and three dedicated terminals: Gate, Source, and Drain. The straight-lead variant enables manual or automated placement with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PD55035-E, the PD55035S-E offers identical RF performance with straight-lead compatibility for simplified assembly, while the MRF6P21180HR3 delivers higher power at the cost of increased system complexity and thermal management overhead.

Availability

PD55035S-E is available at Aetrix Electronics and suitable for FM/AM mobile radio transmitters, land mobile radio base stations, UHF public safety transmitters, and ISM band industrial amplifiers requiring stable component supply across production lifecycles.

Supply support for PD55035S-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, designing and manufacturing analog, microcontroller, power, and RF solutions for industrial, automotive, and consumer markets.

PD55035S-E belongs to ST's LdmoST plastic family of RF power transistors, engineered specifically for high-gain, broadband commercial and industrial amplification up to 1 GHz with emphasis on thermal reliability and SMD manufacturability.

FAQ

What is the maximum continuous drain current for PD55035S-E?

The absolute maximum drain current is 7 A, but the recommended continuous operating limit is 3 A at TC = 70°C, based on thermal derating curves and 95 W power dissipation rating. At 35 W RF output, typical DC drain current remains below 3 A under Class AB bias conditions.

Can PD55035S-E be used at frequencies above 1 GHz?

Electrical characterization extends to 1500 MHz, with verified S-parameters showing usable gain (S21 > 0.26) and stability (|S11| < 0.98) up to 1.5 GHz. However, output power drops significantly beyond 1 GHz - 35 W is specified only up to 500 MHz, and design validation is required for 1–1.5 GHz operation.

How does the PowerSO-10RF straight-lead package differ from the formed-lead version?

The straight-lead variant (PD55035S-E) features vertical leads for compatibility with wave soldering and manual prototyping, whereas the formed-lead version (PD55035-E) uses gull-wing leads optimized for reflow soldering. Both share identical die, thermal performance, and RF characteristics per datasheet Table 1.

Is PD55035S-E qualified for automotive applications?

While not AEC-Q101 qualified, PD55035S-E is widely deployed in automotive mobile radios due to its 165°C junction rating, 1.0 °C/W thermal resistance, and PowerSO-10RF package robustness. ST recommends validating board-level thermal performance and vibration resistance per ISO 16750 for specific vehicle integration.