NXP Semiconductors A2T18S261W12NR3

Overview

A2T18S261W12NR3 from NXP Semiconductors is an RF power LDMOS transistor designed for cellular base station amplifiers operating in the 1805–1880 MHz band. It delivers 56 W average output power at 28 Vdc with 34.8% drain efficiency and 18.2 dB power gain at 1880 MHz under single-carrier W-CDMA conditions (PAR = 9.9 dB, 0.01% CCDF probability).

For engineers reviewing the A2T18S261W12NR3 datasheet, A2T18S261W12NR3 pinout, A2T18S261W12NR3 application, or A2T18S261W12NR3 equivalent, key selection criteria include its 1805–1880 MHz instantaneous bandwidth, ability to withstand 10:1 VSWR load mismatch at 32 Vdc, –10 dB input return loss at 1880 MHz, and optimized Doherty amplifier topology support.

Technical Context

This N-channel enhancement-mode lateral MOSFET operates as a high-efficiency RF power amplifier stage in macrocell and remote radio head (RRH) transmitters. Its internal input/output matching enables direct integration into 50 Ω systems without external impedance transformers, while the VBW (bias network) pins support stable gate biasing under wideband modulation.

The device features a thermally robust OM-880X-2L2L plastic over-molded package with exposed source on the backside, enabling low 0.23 °C/W junction-to-case thermal resistance at 56 W CW operation. It supports Class AB and Class C operation via extended –6.0 Vdc gate-source voltage range and maintains <0.5 dB gain flatness across 75 MHz bandwidth at rated output power.

Key Specifications

Pinout & Package

Package: OM-880X-2L2L - over-molded plastic package with exposed source terminal on backside; 56 mm tape width, 13-inch reel (R3 suffix); moisture sensitivity level 3 (peak reflow 260 °C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AFM30L030N and MRFE6VP6300H, the A2T18S261W12NR3 provides optimal balance of bandwidth coverage (1805–1880 MHz), 56 W average power, and thermal efficiency (0.23 °C/W) specifically for Band 3 FDD-LTE uplink in space-constrained RRH and micro-macro hybrid deployments.

Availability

A2T18S261W12NR3 is available at Aetrix Electronics and suitable for cellular infrastructure, remote radio head (RRH), and macrocell base station applications requiring stable component supply, long-term lifecycle support, and traceable sourcing for production ramp-up.

Supply support for A2T18S261W12NR3 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 is a global semiconductor leader specializing in secure connectivity solutions for automotive, industrial, and communication infrastructure markets.

The A2T18S261W12NR3 belongs to NXP's AIRFAST RF Power LDMOS family, engineered for high-efficiency, wideband cellular base station amplifiers operating in licensed frequency bands from 700 MHz to 3.8 GHz.

FAQ

What is the maximum continuous drain voltage rating for A2T18S261W12NR3?

The A2T18S261W12NR3 has a maximum drain-source voltage rating (VDSS) of +65 Vdc. This rating allows safe operation under transient overvoltage conditions common in RF amplifier bias circuits, including switching transients and load mismatch reflections. The device is specified for 32 Vdc operating voltage (VDD), and its 65 Vdc VDSS margin ensures robustness against voltage spikes during VSWR events or power supply overshoot. Always observe the absolute maximum ratings in Table 1 of the A2T18S261W12NR3 datasheet for reliable long-term operation.

Does A2T18S261W12NR3 require external input/output matching networks?

No, the A2T18S261W12NR3 is internally matched for both input and output in a 50 Ω system across its 1805–1880 MHz operating band. This eliminates the need for discrete matching components in standard test fixtures and simplifies PCB layout. However, external harmonic filters and bias decoupling remain necessary - as shown in Figure 2 of the A2T18S261W12NR3 datasheet - to meet spectral mask requirements and ensure stable gate bias under modulation.

What is the thermal resistance specification for A2T18S261W12NR3, and how is it measured?

The A2T18S261W12NR3 has a junction-to-case thermal resistance (RθJC) of 0.23 °C/W, measured at 81°C case temperature, 56 W CW output, 28 Vdc, 1500 mA IDQ, and 1840 MHz. This value is derived per AN1955 methodology using calibrated thermal measurement fixtures. The low RθJC enables efficient heat transfer to the heatsink through the exposed source pad on the backside of the OM-880X-2L2L package, supporting high-reliability operation in thermally constrained RRH enclosures.

Can A2T18S261W12NR3 be used in Doherty amplifier configurations?

Yes, the A2T18S261W12NR3 is explicitly optimized for Doherty amplifier topologies. Its extended negative gate-source voltage range (–6.0 Vdc), high linearity (–34.6 dBc ACPR), and VBW resonance at 100 MHz support precise bias control and broadband combining in asymmetric Doherty designs. NXP application notes and reference layouts confirm its use as the main amplifier arm in commercial Band 3 Doherty PA modules, delivering 34.8% drain efficiency at 56 W average output.

What does the "R3" suffix indicate in A2T18S261W12NR3?

The "R3" suffix in A2T18S261W12NR3 denotes the packaging configuration: 250 units per reel, 56 mm tape width, and 13-inch reel diameter. This is the standard shipping format for surface-mount assembly in high-volume cellular infrastructure manufacturing. The R3 designation is defined in Table 6 of the A2T18S261W12NR3 datasheet and aligns with IPC/JEDEC standards for moisture sensitivity level 3 devices requiring bake-before-reflow if exposed beyond floor life.