MRF21125R3 - 125W, 28V RF Power MOSFET | NXP Semiconductors
Teilenummer: MRF21125R3 ✗ Abgekündigt| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $165 | $165,00 |
| 10 | $152 | $1.520,00 |
| 100 | $138 | $13.800,00 |
| 500 | $124.5 | $62.250,00 |
| 1.000 | $112 | $112.000,00 |
MRF21125R3 Übersicht
A RF power MOSFET is a specialized metal-oxide-semiconductor field-effect transistor optimized to deliver large amounts of RF energy at high frequencies. Within the wireless transmitter hierarchy, the device sits at the final PA (power amplifier) stage, after the driver amplifier and before the bandpass filter and antenna. Compared with earlier bipolar RF transistors, lateral MOSFETs offer higher gain, better thermal stability, and easier broadband matching, which is why they dominate modern cellular base-station PAs.
Key features of the MRF21125R3 include a typical quiescent current of 1600 mA for Class AB operation, a maximum dissipated power of 330 W, an absolute maximum junction temperature of 200 °C, and a two-terminal flange configuration. The lateral N-channel architecture supports stable operation across wide duty cycles and is suitable for both continuous-wave and pulsed waveforms used in 3G multi-carrier environments.
From a system standpoint, the MRF21125R3 is typically biased from a regulated 28 V supply and matched with microstrip or stripline networks on a low-loss PCB such as Rogers RO4003C. Designers pair it with a dedicated gate driver and a circulator/isolator to protect the device from VSWR excursions. The ceramic NI-880 package provides a low thermal resistance path to the heatsink, which is essential because at 125 W RF output and ~50% efficiency roughly 125 W is dissipated as heat.
Typical applications include W-CDMA macro-cell base-station power amplifiers, PCS/cellular infrastructure, multicarrier TDMA/CDMA line-ups, and WLL (wireless local loop) transceivers. It can also serve as a final stage in PCN/cellular radio amplifiers when biased in Class AB.
When designing with this device, ensure the heatsink is sized for at least 200 W continuous dissipation and that the input/output matching networks are tuned for the 2110–2170 MHz band. Always operate below the 65 V drain breakdown and respect the 200 °C junction limit to maintain long-term reliability.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes that complement the manufacturer datasheet for engineers evaluating the MRF21125R3.
Drop-in-Alternativen für MRF21125R3 – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
MRF21125SR3
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MRF21125R3 Grenzwerte & elektrische Eigenschaften
| Manufacturer | NXP Semiconductors (formerly Freescale Semiconductor) |
| Part Family | MRF21125 |
| Transistortyp | Lateral N-Channel Enhancement-Mode MOSFET |
| Application Band | 2110 MHz to 2170 MHz |
| Output Power | 125 W (typical, W-CDMA) |
| Power Gain | 13 dB (typical) |
| Drain Supply Voltage (VDD) | 28 V |
| Drain Current (IDQ, typical) | 1600 mA |
| Breakdown Voltage | 65 V |
| Maximum Power Dissipation | 330 W (absolute) |
| Maximum Junction Temperature | 200 °C |
| Gehäuse / Bauform | NI-880H-2L (CASE 465B-03, Style 1) |
| Montageart | Chassis / Flange Mount (ceramic) |
| Configuration | Single N-channel MOSFET |
| Terminals | 2 |
| Surface Mount | No (through-flange) |
| Highest Frequency Band | S-Band (subset, 2.11–2.17 GHz) |
| Technology | Lateral DMOS (LDMOS) |
| Lifecycle Note | Removed from active portfolio per NXP product page |
MRF21125R3 Pin-Konfiguration
| Pin 1 | Drain (RF Output) — Drain terminal; RF output via ceramic lead, bolt to matching network |
| Pin 2 | Source (Flange) — Source terminal connected to metal mounting flange; bolt to heatsink for ground and thermal path |
| Pin 3 | Gate (Internal/Bond-wire) — Gate is bonded internally to a feedthrough or marked gate pad per CASE 465B-03 |
DC Sicherer Arbeitsbereich (estimated envelope)
Typische Anwendungen
MRF21125R3 ist geeignet für 6 Anwendungs: W-CDMA Macro Base Station Power Amplifier, PCS / Cellular Radio Infrastructure, Multicarrier TDMA / CDMA Amplifier, Wireless Local Loop (WLL) Transmitter, Industrial RF Heating / Drying Transmitter, Legacy W-CDMA Base Station Repair / Maintenance.
W-CDMA Macro Base Station Power Amplifier
The MRF21125R3's 125 W output, 13 dB gain, and 28 V operation make it an ideal final-stage PA for 2110–2170 MHz W-CDMA macro-cell base stations. Its lateral N-channel LDMOS architecture delivers the linearity required for W-CDMA modulation while supporting the two-carrier test conditions specified in the NXP datasheet at VDD = 28 V and IDQ = 1600 mA. Placed after a driver amplifier and before the duplexer, it provides the RF power headroom macro cells need while keeping adjacent-channel leakage within 3GPP specifications. Compared with bipolar transistors of the same power class, the MRF21125R3 offers higher gain and better broadband matching tolerance, simplifying the output matching network on a low-loss substrate such as Rogers RO4003C.
Empfohlen
PCS / Cellular Radio Infrastructure
Designed for Class AB service in the PCN/PCS and cellular bands, the MRF21125R3 is suitable for 1900 MHz PCS and 2100 MHz cellular radio base-station transmitters that overlap its 2110–2170 MHz passband. Its 65 V breakdown gives ample margin above the 28 V rail for transient overshoot, while the 13 dB typical gain reduces the gain burden on the upstream driver. Engineers commonly bias it at IDQ = 1600 mA and use microstrip matching on a ceramic-PCB substrate. The lateral MOSFET construction offers stable gain across temperature, which is critical for outdoor base-station equipment subject to wide thermal swings.
Empfohlen
Multicarrier TDMA / CDMA Amplifier
The MRF21125R3 is explicitly rated for multicarrier TDMA and CDMA amplifier applications per the NXP datasheet. Its 125 W CW-class power handling and 28 V operation make it suitable for amplifier line-ups that combine multiple carriers into a common PA, where linearity and thermal stability are paramount. The two-carrier W-CDMA performance curves published in the datasheet provide realistic data for adjacent-channel power ratio (ACPR) budgeting. A circulator at the output protects the device from load-pull damage when one carrier band experiences VSWR anomalies.
Empfohlen
Wireless Local Loop (WLL) Transmitter
WLL base-station radios operating at 2.1–2.2 GHz can use the MRF21125R3 as the final PA stage. Its 125 W output covers the link-budget requirements of fixed-wireless customer-premises equipment served from a central base station, while the 28 V rail simplifies compliance with the standard -48 V telecom bus through a single DC-DC converter. The NI-880H-2L flange package bolts directly to a chassis-mounted heatsink, supporting continuous-duty operation. Compared with smaller discrete RF MOSFETs, the MRF21125R3 consolidates the final-stage gain into a single device, reducing PCB complexity and bill of materials.
Empfohlen
Industrial RF Heating / Drying Transmitter
Beyond cellular, the MRF21125R3's 2110–2170 MHz coverage and 125 W continuous-wave capability lend themselves to industrial RF heating, drying, and plasma-excitation systems operating near 2.1 GHz. The 28 V supply is easy to derive from industrial 380 V DC inputs, while the ceramic NI-880 flange supports the heavy heatsinking that continuous industrial duty requires. Designers should re-characterize the matching networks for the specific industrial load impedance rather than reuse cellular matching data. The 65 V breakdown provides safety margin for inductive load transients common in plasma and drying applications.
Empfohlen
Legacy W-CDMA Base Station Repair / Maintenance
Because the MRF21125R3 has been removed from NXP's active portfolio but remains in service across thousands of legacy W-CDMA sites, it is still sought for board-level repair and field maintenance. Stocked identical part per NXP's datasheet, technicians can replace a single failed PA in an installed amplifier module without re-tuning the surrounding 50 Ω network, which saves significant operator downtime. Rochester Electronics and other authorized channels continue to allocate inventory to support these legacy networks. For new deployments, NXP recommends evaluating its current LDMOS portfolio for higher efficiency and longer-term supply security.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für MRF21125R3 – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | MRF21125SR3 |
|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors |
| Package | NI-880H-2L (CASE 465B-03) | NI-880H-2L (CASE 465B-03) - same |
| Frequency Range | 2110-2170 MHz | 2110-2170 MHz |
| Output Power | 125 W | 125 W |
| Power Gain | 13 dB | 13 dB |
| Drain Voltage | 28 V | 28 V |
| Breakdown Voltage | 65 V | 65 V |
| Quiescent Current (typical) | 1600 mA | 1600 mA |
| Maximum Dissipation | 330 W | 330 W |
| Lifecycle Status | NRND (removed from active portfolio) | NRND (removed from active portfolio) |
Wichtigste Unterscheidungsmerkmale
- Same-die drop-in equivalent within the NXP family (vs. MRF21125SR3)
- High power density in NI-880H-2L ceramic flange package (vs. Smaller-packaged LDMOS devices)
- Optimized for two-carrier W-CDMA linearity (vs. Single-carrier-only RF MOSFETs)
Designhinweise
Estimated: at 125 W RF output and approximately 50% drain efficiency, the MRF21125R3 dissipates roughly 125 W as heat. With a 200 °C maximum junction and a target 110 °C junction for long life, the junction-to-heatsink thermal budget is about 1 °C/W. Use a forced-air or liquid-cooled heatsink and verify with a thermal sensor at the flange. The NI-880H-2L ceramic flange must be bolted flat to the heatsink with thermal compound to minimize contact resistance.
Use a low-loss RF substrate such as Rogers RO4003C or RO4350B for the input and output matching networks. Keep gate and drain traces short and away from each other to minimize feedback. Place bias feed resistors and bypass capacitors (100 pF, 1 nF, 10 uF in parallel) directly at the gate and drain leads. Provide a solid ground plane stitched generously with vias around the matching network. Estimated microstrip dimensions for 50 Ω on 0.508 mm RO4003C are about 1.15 mm wide.
Do not exceed 65 V on the drain even transiently - VSWR-induced overshoot is a frequent failure mode and requires a drain clamp or output isolator. Ensure the gate is biased through a sequenced supply that brings gate voltage up before drain voltage to avoid partial-turn-on oscillations. Always include a gate protection resistor and a drain-to-gate ESD network. When retrofitting into an existing amplifier, re-verify the quiescent current and matching network tuning because the SR3 variant may have slightly different S-parameters.
Compliance-Informationen
Compliance certifications were not provided in the verified web data; values set to unknown pending datasheet or manufacturer declaration. The part is a ceramic-packaged RF power transistor primarily used in fixed telecom infrastructure, not automotive (AEC-Q100 not applicable).
