NXP Semiconductors AFT26H250W03SR6

Overview

AFT26H250W03SR6 from NXP Semiconductors (formerly Freescale) is a 50 W asymmetrical Doherty RF power LDMOS transistor designed for cellular base station amplifiers operating in the 2496–2690 MHz band. It delivers 14.4 dB typical power gain, 44.9% drain efficiency, and –33.8 dBc ACPR at 2590 MHz under W-CDMA single-carrier conditions (28 Vdc, 50 W avg., PAR = 9.9 dB). Its dual-gate architecture supports carrier-peaking operation with independent gate biasing for digital predistortion linearization.

For engineers reviewing the AFT26H250W03SR6 datasheet, AFT26H250W03SR6 pinout, AFT26H250W03SR6 application, or AFT26H250W03SR6 equivalent, this device requires attention to its asymmetric Doherty topology, dual-side thermal resistance (R_θJC = 0.42 °C/W), gate voltage range (–6.0 to +10 Vdc), and mandatory tied VDDA/VDDB supply configuration.

Technical Context

This device implements an integrated asymmetrical Doherty architecture with physically separate carrier (Side A) and peaking (Side B) LDMOS cells in a monolithic NI-1230S-4L2L package. Each side features independent gate terminals (RFinA/VGSA and RFinB/VGSB) and drain terminals (RFoutA/VDSA and RFoutB/VDSB), enabling precise control of quiescent current (IDQA = 700 mA, VGSB = 0.4 Vdc) and load-pull optimized matching.

It is internally matched for 50 Ω systems across 2496–2690 MHz, supports Class AB/Class C hybrid operation via extended negative gate-source voltage range, and is characterized for wide instantaneous bandwidth with <0.3 dB gain flatness over 194 MHz at 50 W avg. output.

Key Specifications

Pinout & Package

Package: NI-1230S-4L2L - RoHS-compliant, thermally enhanced overmolded plastic package with exposed copper die paddle for low-thermal-resistance mounting. Dimensions: 12.7 mm × 12.7 mm × 4.57 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AFM905N and MMRF1022, the AFT26H250W03SR6 offers optimal trade-off between bandwidth coverage (2496–2690 MHz), integrated matching, and proven Doherty linearity - making it the preferred choice for LTE-Advanced macrocell upgrades where footprint, thermal management, and DPD compatibility are prioritized over raw GaN power density.

Availability

AFT26H250W03SR6 is available at Aetrix Electronics and suitable for macrocell base station transmitters, remote radio heads, massive MIMO active antenna units, and RF test bench reference designs requiring stable component supply and long-term lifecycle support.

Supply support for AFT26H250W03SR6 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

NXP Semiconductors acquired Freescale in 2015 and continues to develop, manufacture, and support the Airfast RF power portfolio for wireless infrastructure.

The AFT26H250W03SR6 belongs to the Airfast family of asymmetrical Doherty LDMOS transistors engineered specifically for energy-efficient, wideband cellular base station amplifiers operating in licensed sub-6 GHz spectrum.

FAQ

What is the maximum continuous drain voltage rating for the AFT26H250W03SR6?

The AFT26H250W03SR6 has a maximum drain-source voltage rating (V_DSS) of +65 Vdc and –0.5 Vdc. This rating applies under all operating conditions including load mismatch events; operation beyond these limits risks permanent device degradation. The AFT26H250W03SR6 is rated for 32 Vdc operating voltage (V_DD), with derating required above case temperature of 25 °C.

Can the AFT26H250W03SR6 be operated with separate VDDA and VDDB supplies?

No - the AFT26H250W03SR6 requires VDDA and VDDB to be tied together and powered by a single DC supply, as explicitly stated in Tables 4 and 5 of the datasheet. Attempting independent supply routing violates the internal current-sharing design and may cause thermal imbalance or premature failure. The AFT26H250W03SR6 pinout and functional test conditions assume unified 28 Vdc bias.

What is the significance of the "R6" suffix in AFT26H250W03SR6?

The "R6" suffix in AFT26H250W03SR6 indicates tape-and-reel packaging: 150 units per reel, 56 mm tape width, and 13-inch reel diameter. This packaging format is optimized for automated SMT placement in high-volume RF power amplifier module manufacturing. The R6 suffix does not denote a functional variant - electrical and thermal specifications match the base AFT26H250W03S part number.

How does the AFT26H250W03SR6 support digital predistortion (DPD) linearization?

The AFT26H250W03SR6 supports DPD through its asymmetrical Doherty architecture, independent gate biasing (V_GSA, V_GSB), and wide instantaneous bandwidth (2496–2690 MHz). Its measured AM/PM distortion is ≤–22° across the band, and its –33.8 dBc ACPR at 50 W avg. provides sufficient linearity headroom for third-order DPD convergence. The AFT26H250W03SR6 is characterized with IQ-magnitude clipping and 9.9 dB PAR signals per 3GPP standards.

What thermal interface requirements apply to the AFT26H250W03SR6 package?

The AFT26H250W03SR6 uses an NI-1230S-4L2L package with an exposed copper die paddle requiring low-thermal-resistance mounting. To achieve the specified R_θJC = 0.42 °C/W, a thermal interface material (TIM) with ≤0.15 °C·in²/W resistance and uniform pressure ≥250 psi must be applied between the paddle and heatsink. Thermal vias under the paddle and solder paste stencil design per IPC-7351B are mandatory for production reliability.