MRF5S21045NBR1 - 10W RF Power LDMOS, 2110-2170 MHz | NXP
MPN: MRF5S21045NBR1 ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $38.5 | $38.50 |
| 10 | $34.65 | $346.50 |
| 100 | $30.9 | $3,090.00 |
| 500 | $27.5 | $13,750.00 |
| 1,000 | $25.2 | $25,200.00 |
MRF5S21045NBR1 Overview
An RF power LDMOS (Laterally Diffused MOSFET) is a specialized power transistor designed for radio-frequency amplification. LDMOS sits within the broader power MOSFET family, optimized for high-frequency, high-efficiency linear amplification where standard vertical MOSFETs lose performance. These devices are widely used in cellular infrastructure, broadcast transmitters, and industrial RF heating because they deliver high gain, good linearity, and ruggedness at modest cost.
Key features include 14.5 dB typical power gain at 2.12 GHz, a high drain efficiency suited for W-CDMA signal envelopes, integrated ESD protection, and a thermally enhanced ceramic-style over-molded package. The lateral structure minimizes parasitic capacitances, enabling broadband operation while maintaining stable linearity under multicarrier load conditions.
Technically, the MRF5S21045NBR1 uses a laterally diffused drain architecture with an internal input matching network that simplifies external circuitry. Per the NXP datasheet, the device is characterized for W-CDMA base station driver and final stages, supports TDMA, CDMA, and multicarrier amplifier applications, and is optimized for Class AB operation in PCN-PCS/cellular radio and wireless local loop (WLL) applications.
Typical applications include W-CDMA base station power amplifiers (PA), PCN/PCS cellular infrastructure driver stages, wireless local loop (WLL) transceivers, and multicarrier power amplifier modules used in 3G/4G macrocell radios operating in the 2110-2170 MHz band.
When designing with this part, ensure the heatsink thermal resistance keeps the junction below the rated maximum under worst-case multicarrier W-CDMA load. Source matching should follow the evaluation board layout precisely, as the TO-272 WB-4 package is footprint-dependent for stable RF performance.
This page synthesizes distributor pricing, drop-in NXP alternates in the same TO-272 WB-4 footprint, and practical heatsink and bias-tee design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for MRF5S21045NBR1 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MRF5S21045NBR1 (same form factor and footprint) — differing in Mounting Type, Transistor Type, Application, Configuration, Frequency Band.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MRF5S21045NR1
✅ Drop-In📋 Reference alternative (not in catalog)
MRF6S18100NBR1
✅ Drop-In✓ In Stock
$68.9 / Unit
View Datasheet →MRF5S19060NBR1
✅ Drop-In✓ In Stock
$25.4 / Unit
View Datasheet →MRF5S21045NBR1 Maximum Ratings & Electrical Characteristics
| Transistor Type | N-Channel Enhancement-Mode Lateral MOSFET (LDMOS) |
| Frequency Band | 2110 MHz to 2170 MHz |
| Test Frequency | 2.12 GHz |
| Output Power (Avg) | 10 W |
| Power Gain | 14.5 dB (typical at 2.12 GHz, 28 V) |
| Drain-Source Voltage (Max Rated) | 68 V |
| Test Supply Voltage (Vdd) | 28 V |
| Test Current | 500 mA |
| Package | TO-272 WB-4 (over-molded plastic) |
| Supplier Device Package | TO-272 WB-4 |
| Mounting Type | Surface Mount |
| Operating Mode | Class AB |
| Application | W-CDMA base station, TDMA/CDMA, multicarrier amplifier |
| Technology | Laterally Diffused MOS (LDMOS) |
| Compliance | RoHS (status per distributor listing - confirm at order) |
| Manufacturer | NXP USA Inc. (formerly Freescale Semiconductor) |
MRF5S21045NBR1 Pin Configuration
| Pin 1 | DRAIN — Drain (RF output) - main power path |
| Pin 2 | GATE — Gate - RF input, requires DC bias |
| Pin 3 | SOURCE — Source - connected to ground via PCB thermal pad |
| Pin 4 | NC — Not connected (or thermal pad - per datasheet) |
MRF5S21045NBR1 RF Safe Operating Region
Typical Applications
MRF5S21045NBR1 is suitable for 6 applications: W-CDMA Base Station Final Stage, PCN/PCS Cellular Radio Driver, Multicarrier Power Amplifier Module, Wireless Local Loop (WLL) Transceiver, TDMA/CDMA Power Amplifier Front End, Industrial RF Heating / Plasma Driver.
W-CDMA Base Station Final Stage
The MRF5S21045NBR1 is engineered for 2110-2170 MHz W-CDMA base station final-stage amplifiers per its NXP datasheet. Its 14.5 dB gain drives 10 W of clean W-CDMA average power when biased in Class AB from 28 V, supporting the 3GPP downlink mask with adequate margin. Drain efficiency near the 1 dB compression point is suitable for multicarrier UMTS environments, and the TO-272 WB-4 package provides low-inductance grounding essential at these frequencies. Heatsink mass and PCB copper area should be sized to keep junction rise below the rated maximum under continuous multicarrier load.
Recommended
PCN/PCS Cellular Radio Driver
In cellular PCN/PCS radio chains, the MRF5S21045NBR1 functions as a driver or final stage running from a 28 V rail. Per the NXP datasheet, Class AB operation preserves linearity for non-constant-envelope signals, while the 14.5 dB gain substantially reduces the required drive from upstream gain blocks. Source matching follows the reference evaluation board layout to maintain unconditional stability across the 2110-2170 MHz band under varying VSWR. Bypass capacitors on the drain feed must be placed within 2 mm of the package pad to suppress parasitic resonances.
Recommended
Multicarrier Power Amplifier Module
The MRF5S21045NBR1 supports multicarrier amplifier (MCPA) applications for 3G macrocell radios. NXP datasheet states it tolerates simultaneous multicarrier load without gain droop, and the 68 V drain rating provides margin beyond the 28 V supply for transient peaks. A bias tee on the gate sets the quiescent current to 500 mA at room temperature; thermal compensation can be added with a thermistor at the heatsink surface. The TO-272 WB-4 lead geometry enables excellent RF grounding even on FR-4 substrates.
Recommended
Wireless Local Loop (WLL) Transceiver
For WLL fixed-wireless-access transceivers operating in the 2110-2170 MHz band, the MRF5S21045NBR1 delivers the 10 W of average transmit power required to close the link over the 5-10 km customer premises. The 14.5 dB gain reduces the bill-of-materials for upstream gain stages, and the Class AB bias point achieves acceptable linearity for the simpler QPSK/16-QAM modulations used in fixed-wireless links. Heatsink design must account for outdoor cabinet ambient of 50-65 C typical.
Recommended
TDMA/CDMA Power Amplifier Front End
The MRF5S21045NBR1 is suitable for legacy TDMA and CDMA power amplifier front ends where the 2110-2170 MHz band overlaps with certain UMTS/coexistence channels. NXP datasheet compatibility ratings allow operation in constant-envelope back-off modes for TDMA links or near-saturation for CDMA carriers. Effective load-line matching at 28 V maintains efficiency above 40% at the typical 8-9 W operating point, well within the 10 W average rating.
Recommended
Industrial RF Heating / Plasma Driver
Although the NXP datasheet is targeted at cellular base stations, the MRF5S21045NBR1 functions competently as a 10 W continuous RF source for industrial plasma-generation or small-scale RF heating in the 2.1 GHz range. Its 68 V drain rating tolerates the higher reflected power typical of mismatched plasma loads, provided the heatsink absorbs the resulting dissipation. A directional coupler and circulator between the device and load are recommended to protect the junction during transient load shifts.
Recommended
Recommended Products Summary
Engineering reference data for MRF5S21045NBR1 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MRF5S21045NR1 | MRF6S18100NBR1 | MRF5S19060NBR1 |
|---|---|---|---|---|
| Package | TO-272 WB-4 | TO-272 WB-4 - same | TO-272 WB-4 - same | TO-272 WB-4 - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Frequency Band | 2110-2170 MHz | 2110-2170 MHz - same | 1805-1880 MHz | 1930-1990 MHz |
| Output Power (Avg) | 10 W | 10 W - same | 100 W | 12 W |
| Test Supply Voltage | 28 V | 28 V - same | 28 V | 28 V |
| Technology | LDMOS | LDMOS - same | LDMOS | LDMOS |
Key Differentiators
- Highest narrow-band frequency coverage (vs MRF5S19060NBR1)
- Lower power than MRF6S18100NBR1 makes it suitable for driver stage (vs MRF6S18100NBR1)
- Tape-and-reel orientation optimized for SMT lines (vs MRF5S21045NR1)
Design Notes
Estimated thermal design: at 10 W output power in Class AB, the device consumes ~22 W of DC power from the 28 V rail, dissipating ~12 W as heat through its TO-272 WB-4 thermal pad. Per the NXP datasheet, the heatsink thermal resistance must keep junction temperature below 200 C. Conservative design uses a 1.5 C/W heatsink with 100 CFM forced air; the PCB copper pour under the thermal pad should be at least 1 oz copper over a 30x30 mm area to spread heat before reaching the heatsink.
Per the NXP datasheet evaluation board layout, source bonding (lead 3 / thermal pad) must be directly underneath the device to the top-side ground plane using multiple vias. Drain (lead 1) and gate (lead 2) microstrip traces should be 50 ohm controlled-impedance on the substrate (typically 0.5-0.8 mm RO4350B). The DC bias feed on the drain should use a quarter-wavelength microstrip choke or a discrete bias tee rated for 5 A minimum.
DO NOT exceed 28 V on the test supply without re-derating power - the device is rated at 28 V for 10 W output. Exceeding the 68 V Vds maximum will destroy the drain-source junction. Also, never operate without a heatsink properly attached; at 500 mA quiescent and full drive, the device self-destructs in under 10 seconds if thermally unanchored. Always sequence the gate bias BEFORE the drain supply during turn-on.
The TO-272 WB-4 source-lead inductance is intentionally minimized in the package, but external source vias still contribute to common-mode gain ripple. Per the NXP datasheet, multiple ground vias in a 4-6 pattern around the source pad reduce this effect. For stability, add 2-6 ohms of gate series resistance if the device shows low-frequency oscillations during initial bias-up.
Compliance Information
Compliance status not explicitly listed in the verified distributor/NXP datasheet snippet. Confirm RoHS/REACH status with NXP or the distributor at order time. AEC-Q100 is not applicable - this is an RF power device, not an automotive-qualified automotive logic part.
