NXP Semiconductors MRF6S9045NR1

Overview

MRF6S9045NR1 from Freescale Semiconductor is an N-channel enhancement-mode lateral MOSFET RF power transistor designed for broadband base station amplifiers operating up to 1000 MHz. It delivers 10 W average output power at 880 MHz under N-CDMA conditions (V_DD = 28 V, I_DQ = 350 mA), achieves 22.7 dB power gain and 32% drain efficiency, and supports GSM EDGE (16 W avg., 20 dB gain, 46% efficiency) and GSM (45 W CW, 68% efficiency) applications in 921–960 MHz bands.

For engineers reviewing the MRF6S9045NR1 datasheet, MRF6S9045NR1 pinout, MRF6S9045NR1 application, or MRF6S9045NR1 equivalent, key selection criteria include its TO-270-2 plastic package with integrated ESD protection, 225°C junction rating, 5:1 VSWR tolerance at 45 W CW, and verified performance in commercial 28 V base station infrastructure requiring high linearity and thermal robustness.

Technical Context

This device operates as a common-source amplifier with characterized series-equivalent large-signal impedance parameters (e.g., Z_source = 3.16 + j1.33 Ω, Z_load = 0.45 + j0.60 Ω at 880 MHz). Its lateral LDMOS structure enables stable operation under mismatched loads, including 5:1 VSWR at full 45 W CW output.

It features integrated ESD protection rated Class 1A HBM, Class A MM, and Class IV CDM per JESD22 standards, and is qualified to Moisture Sensitivity Level 3 (peak reflow 260°C). The R1 suffix denotes tape-and-reel packaging: 500 units per 24 mm wide, 13-inch reel for TO-270-2.

Key Specifications

Pinout & Package

Package: TO-270-2 (Case 1265-09, Style 1), plastic overmolded, lead-free (N suffix), bolt-down or surface-mount capable. Thermal resistance junction-to-case is 1.0°C/W at 45 W CW.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MRF6S9045NR1, MRFE6S9045NR1 offers identical form-fit-function with enhanced reliability, while MRF6P9045GNR1 trades pin compatibility for higher voltage and power capability-requiring board-level changes but enabling more demanding PA architectures.

Availability

MRF6S9045NR1 is available at Aetrix Electronics and suitable for macrocell base station transmitters, GSM EDGE final amplifiers, N-CDMA infrastructure, multi-standard reconfigurable PAs, and broadband RF power stages requiring stable component supply and proven thermal robustness.

Supply support for MRF6S9045NR1 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

Freescale Semiconductor (now part of NXP Semiconductors) was a leading designer of RF power transistors for wireless infrastructure, emphasizing high-efficiency, thermally robust, and production-ready solutions.

The MRF6S9045NR1 belongs to Freescale's MRF6S family of lateral N-channel MOSFETs engineered specifically for 28 V broadband base station amplifiers operating up to 1 GHz with stringent linearity and reliability requirements.

FAQ

What is the maximum continuous drain current rating for the MRF6S9045NR1?

The MRF6S9045NR1 does not specify a maximum continuous drain current (I_D) rating directly; instead, its safe operating area is defined by maximum ratings including V_DSS = +68 V, junction temperature limit of 225°C, and thermal resistance R_θJC = 1.0°C/W. Under typical 45 W CW operation at 28 V, the average drain current is approximately 1.6 A, consistent with its quiescent current I_DQ = 350 mA and pulsed characteristics shown in Figure 5. Always verify current limits using the SOA curves in the MRF6S9045N datasheet Rev. 4.

Does the MRF6S9045NR1 require external ESD protection in PCB layout?

No, the MRF6S9045NR1 includes integrated ESD protection rated Class 1A per JESD22-A114 (HBM), Class A per JESD22-A115 (MM), and Class IV per JESD22-C101 (CDM). This eliminates the need for discrete ESD diodes on gate or drain lines in standard handling and operational environments. However, proper grounding, controlled ESD-safe assembly practices, and adherence to JEDEC MSL-3 reflow guidelines remain essential to preserve this built-in protection in the MRF6S9045NR1.

What is the recommended gate bias voltage range for the MRF6S9045NR1 in Class AB operation?

The MRF6S9045NR1 specifies a gate quiescent voltage V_GS(Q) of 2.0–4.0 Vdc under V_DD = 28 V and I_DQ = 350 mA (Table 5). For stable Class AB operation, a nominal gate bias of 2.9 Vdc is recommended, adjustable within that range to fine-tune I_DQ and optimize linearity versus efficiency. Bias stability is critical: use low-thermal-drift resistors and bypass capacitors as shown in the test circuit (Figure 1) to prevent thermal runaway in the MRF6S9045NR1.

Can the MRF6S9045NR1 be used in 32 V supply applications?

No-the MRF6S9045NR1 has a maximum drain-source voltage rating (V_DSS) of +68 Vdc, but its safe operating area and published performance data (gain, efficiency, linearity) are validated only at V_DD = 28 Vdc. Operating at 32 V exceeds the characterization envelope and risks reduced reliability, unverified distortion performance, and potential instability. For 32 V systems, consider the pin-compatible MRF6P9045GNR1, which is rated for 100 V_DSS and characterized at 32 V in the MRF6P9045G datasheet.

Is the MRF6S9045NR1 still in active production or obsolete?

The MRF6S9045NR1 is listed as replaced by MRFE6S9045NR1 per Device Migration notice PCN12895, and the related MRF6S9045NBR1 variant is explicitly marked "no longer manufactured." While MRF6S9045NR1 may still be available in limited legacy stock, Freescale (now NXP) recommends MRFE6S9045NR1 for all new designs due to identical specifications and improved manufacturing consistency. Aetrix Electronics maintains traceable inventory of MRF6S9045NR1 for legacy repair and continuity, subject to remaining supply.