STMicroelectronics RF5L08350CB4

Overview

RF5L08350CB4 from STMicroelectronics is a 400 W, 50 V internally matched LDMOS RF power transistor optimized for broadband operation from 400 MHz to 1 GHz, delivering 19 dB gain and 61% drain efficiency at 860 MHz under pulsed CW conditions (V_DD = 50 V, I_DQ = 200 mA). It features dual-gate/dual-drain topology, integrated ESD protection (HBM Class 2, CDM Class C3), and is used in UHF TV broadcast amplifiers and RF energy systems.

For engineers reviewing the RF5L08350CB4 datasheet, RF5L08350CB4 pinout, RF5L08350CB4 application, or RF5L08350CB4 equivalent, key selection criteria include its 0.35 °C/W thermal resistance, ±8 V to +10 V gate voltage range, 110 V drain-source breakdown rating, and B4E package's bottom-side source thermal path-critical for high-power RF amplifier thermal design and reliability validation.

Technical Context

This LDMOS FET employs a symmetrical dual-gate/dual-drain structure with isolated source terminals on the bottom side, enabling balanced push-pull or parallel configurations without external current sharing components. Its internal matching network targets 50 Ω input/output impedance across 400–1000 MHz, reducing external tuning complexity.

The device operates with a gate threshold voltage of 1–3 V and quiescent gate voltage of 2–5 V, supporting stable Class AB or Class C biasing. Thermal stability is ensured by low HCI drift and junction temperature capability up to 200 °C, validated under DC and pulsed CW conditions (100 µs pulse width, 10% duty cycle).

Key Specifications

Pinout & Package

The RF5L08350CB4 uses the B4E thermally enhanced flanged ceramic package (27.94 mm × 19.43 mm × 34.04 mm), with source terminals electrically and thermally connected to the metal baseplate for low-impedance heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CGHV1F006S and MRF1K50N, RF5L08350CB4 offers superior broadband 400–1000 MHz performance with factory internal matching, 10:1 VSWR tolerance, and lowest thermal resistance-making it the optimal choice for UHF broadcast, lab amplifiers, and 915 MHz industrial RF energy where ease of integration and thermal margin are critical.

Availability

RF5L08350CB4 is available at Aetrix Electronics and suitable for UHF TV broadcast transmitters, RF energy heating systems, and wideband laboratory test equipment requiring stable component supply and long-lifecycle support.

Supply support for RF5L08350CB4 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 power management, analog, MEMS, and RF solutions for industrial, automotive, and communications markets.

The RF5L series is ST's high-power LDMOS transistor family engineered specifically for broadband RF energy, broadcast, and scientific instrumentation applications demanding >400 W output, >60% efficiency, and rugged thermal performance.

FAQ

What is the maximum continuous drain current rating for RF5L08350CB4?

The device has no specified continuous drain current limit; instead, its safe operating area is defined by absolute maximum ratings: V_DS ≤ 110 V, T_J ≤ 200 °C, and V_DD ≤ 55 V. Under typical 400 W pulsed CW operation (100 µs, 10%), peak drain current reaches ~14.7 A, verified in Table 6 of DS13248 Rev 2.

Can RF5L08350CB4 be operated in Class C mode, and what gate voltage range supports it?

Yes-the device supports Class C operation via its extended gate-source voltage range of -8 V to +10 V, enabling deep cutoff and high efficiency. The datasheet explicitly cites "large positive and negative gate-source voltage range for improved class C operation" in its features section.

Is the B4E package lead-free and RoHS-compliant?

Yes-the B4E package meets ECOPACK® standards with e4-level marking and complies with European Directive 2002/95/EC (RoHS). This is confirmed in Section 5 and the marking composition diagram (Figure 5) of DS13248 Rev 2.

Does RF5L08350CB4 require external gate resistors for stability?

No-stability is ensured by internal gate resistance and optimized layout; the recommended test circuit (Figure 2) uses only external RF chokes and matching capacitors. However, gate stopper resistors (≤10 Ω) are advised in production designs to suppress VHF/UHF parasitic oscillation under mismatched loads.