NXP Semiconductors SA2T18H450W19SR6

Overview

SA2T18H450W19SR6 from NXP Semiconductors (formerly Freescale) is an asymmetrical Doherty RF power LDMOS transistor designed for cellular base station amplifiers operating in the 1805–1880 MHz band. It delivers 89 W average output power at 30 Vdc, achieves 47.7% drain efficiency at 1880 MHz, and maintains –38.8 dBc ACPR under single-carrier W-CDMA conditions with 9.9 dB PAR. Its dual-gate architecture supports carrier-peaking operation in macrocell BTS power amplifier stages.

For engineers reviewing the SA2T18H450W19SR6 datasheet, SA2T18H450W19SR6 pinout, SA2T18H450W19SR6 application, or SA2T18H450W19SR6 equivalent, key selection criteria include its 1805–1880 MHz instantaneous bandwidth, 0.27 °C/W junction-to-case thermal resistance, NI-1230S-4S4S package with 8-pin top-view layout, and compatibility with digital predistortion (DPD) correction systems.

Technical Context

This device implements a monolithic dual-gate LDMOS structure with physically separate carrier (Side A) and peaking (Side B) transistors integrated into a single NI-1230S-4S4S air-cavity package. It operates with independent gate biasing (VGSA = 1.8 Vdc typ., VGSB = 0.9 Vdc) and shared drain supply (VDDA/VDDB tied together at 30 Vdc), enabling precise Doherty load modulation.

The transistor is characterized for W-CDMA signal conditions: 9.9 dB input PAR at 0.01% CCDF probability, 3.84 MHz channel bandwidth, ±5 MHz ACPR offset, and 75 MHz gain flatness of 0.4 dB across the full band. Thermal performance is specified at TC = 73 °C with 89 W avg. output, yielding RθJC = 0.27 °C/W.

Key Specifications

Pinout & Package

The SA2T18H450W19SR6 is housed in the NI-1230S-4S4S air-cavity ceramic package (12.7 mm × 12.7 mm × 4.0 mm), featuring gold-plated copper base, solderable flange, and hermetically sealed cavity for high-power RF reliability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SA2T18H450W19SR6, MRF6VP2600HR6 shifts operating frequency upward and trades bandwidth for raw power, while AFM905S replaces silicon LDMOS with GaN to gain 18 percentage points in drain efficiency-but demands full re-matching and thermal redesign.

Availability

SA2T18H450W19SR6 is available at Aetrix Electronics and suitable for macrocell base stations, remote radio heads, and multi-band BTS combiner stages requiring stable component supply, long-lifecycle support, and traceable sourcing for telecom infrastructure programs.

Supply support for SA2T18H450W19SR6 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 communications markets, with deep heritage in RF power through its acquisition of Freescale.

The SA2T18H450W19SR6 belongs to the Airfast® family of RF power transistors, engineered specifically for energy-efficient, digitally predistorted cellular infrastructure amplifiers operating in licensed sub-6 GHz spectrum.

FAQ

What is the maximum continuous drain voltage rating for the SA2T18H450W19SR6?

The SA2T18H450W19SR6 has a maximum drain-source voltage (VDSS) rating of +65 Vdc and –0.5 Vdc. This rating applies under static conditions and defines the absolute limit for safe DC biasing. In normal operation, the device is rated for 30 Vdc supply (VDD), with transient tolerance up to 32 Vdc as specified in the maximum ratings table. Exceeding +65 Vdc risks irreversible gate oxide breakdown or avalanche failure in the SA2T18H450W19SR6.

Does the SA2T18H450W19SR6 require external input/output matching networks?

No-the SA2T18H450W19SR6 is internally matched on both input and output for 50 Ω operation across 1805–1880 MHz, as confirmed in the datasheet's ordering information footnote. External matching is only required for harmonic termination (e.g., 2nd/3rd harmonics at RFoutA/RFoutB) and VBW resonance tuning. The internal matching eliminates discrete matching components in the main signal path, simplifying layout and improving repeatability in the SA2T18H450W19SR6-based PA design.

What is the gate threshold voltage range for both sides of the SA2T18H450W19SR6?

The SA2T18H450W19SR6 specifies identical gate threshold voltage (VGS(th)) ranges for both carrier (Side A) and peaking (Side B) transistors: 0.8 Vdc to 1.6 Vdc, measured at VDS = 10 Vdc and ID = 200 µAdc (Side A) or 360 µAdc (Side B). This tight VGS(th) distribution ensures consistent turn-on behavior and simplifies bias network design across both paths in the SA2T18H450W19SR6 Doherty configuration.

Can the SA2T18H450W19SR6 operate with independent drain supplies on pins 1/4/5/8?

No-the SA2T18H450W19SR6 requires VDDA and VDDB to be tied together and powered by a single 30 Vdc supply, as explicitly stated in the datasheet's Table 5 footnote and Figure 2 note. Pins 1, 4, 5, and 8 are electrically isolated drain terminals; applying separate voltages violates the device's internal current-sharing architecture and may cause unbalanced operation or thermal runaway in the SA2T18H450W19SR6.

What is the recommended PCB material for the SA2T18H450W19SR6 evaluation board?

The reference test circuit for the SA2T18H450W19SR6 uses Rogers RO4350B laminate (εr = 3.66, thickness = 0.020″), as documented in Table 6 of the datasheet. This material provides stable RF performance, low loss at 1.8 GHz, and reliable thermal conduction to the flange-mounted SA2T18H450W19SR6. Alternative high-frequency laminates like Isola FR408HR or Taconic RF-35 may be used if validated for insertion loss and thermal impedance matching in the SA2T18H450W19SR6 layout.