MRF1513NT1: High-Performance LDMOS RF FET Transistor by NXP

The MRF1513NT1 is a premium LDMOS RF FET transistor manufactured by NXP Semiconductors, a global leader in high-frequency semiconductor solutions. Designed for demanding RF applications, this transistor delivers exceptional performance at 520MHz with 15dB gain and 3W output power. This comprehensive guide explores its specifications, applications, and why it remains a top choice for RF engineers despite being obsolete.

Detailed Product Specifications

Technical Parameters

• Technology: Advanced LDMOS (Laterally Diffused MOSFET)
• Frequency Range: Optimized for 520MHz operation
• Power Output: 3W (30dBm) typical
• Power Gain: 15dB minimum at 520MHz
• Voltage Ratings: 12.5V test voltage / 40V maximum
• Current Capacity: 2A continuous / 50mA test current
• Package: PLD-1.5 (Flange-mounted for optimal thermal management)
• Operating Temperature: -40 C to +150 C

Why LDMOS Technology Matters

LDMOS transistors like the MRF1513NT1 offer significant advantages over traditional MOSFETs for RF applications:

• Higher Power Density: More power in smaller packages
• Improved Linearity: Critical for modern modulation schemes
• Better Thermal Stability: Reduced performance drift
• Lower Feedback Capacitance: Enhanced high-frequency response

Key Applications

1. Amateur Radio Systems

Ideal for HF/VHF transceivers (1.8-520MHz range), particularly in:

• Linear amplifiers for SSB operation
• Driver stages in multi-stage amplifiers
• Portable/mobile radio equipment

2. Commercial RF Equipment

• UHF base station amplifiers
• RF test equipment signal chains
• ISM band (industrial) applications

3. Legacy System Maintenance

Despite being obsolete, the MRF1513NT1 remains valuable for:

• Repairing vintage RF equipment
• Cost-sensitive designs where newer alternatives are prohibitively expensive
• Educational purposes in RF engineering courses

Performance Characteristics

Extensive testing shows the MRF1513NT1 delivers:

Parameter	Value	Conditions
Power Gain	15dB min	520MHz, 12.5V
Efficiency	40-50%	Typical Class AB operation
Input VSWR	2:1	Typical without matching
Thermal Resistance	3 C/W	Junction-to-case

Design Considerations

Biasing Requirements

For optimal performance:

• Gate voltage: 3.5-4V for Class AB operation
• Drain voltage: 12-28V typical (40V absolute max)
• Quiescent current: 50-100mA recommended

Matching Networks

Recommended matching approaches:

• Input: LC network for 50 match
• Output: Harmonic filtering recommended
• Use RF simulation tools for optimal performance

Obsolete Status: What It Means

While marked obsolete by NXP, the MRF1513NT1:

• Remains available through authorized distributors
• Has proven reliability in field applications
• Offers cost advantages versus newer alternatives

Recommended alternatives for new designs include NXP's MRF1K50H and MRF101AN.

Where to Buy

Genuine MRF1513NT1 transistors can be sourced through:

• Authorized NXP distributors
• Specialist RF component suppliers
• Verified surplus electronics vendors

Conclusion

The MRF1513NT1 represents NXP's expertise in RF power transistors, offering robust performance at 520MHz. Its combination of 15dB gain, 3W output, and LDMOS reliability makes it particularly valuable for:

• Maintaining legacy RF systems
• Cost-sensitive amplifier designs
• Educational and experimental projects

For engineers requiring this specific part number, we recommend verifying authenticity and considering inventory for long-term projects. New designs should evaluate NXP's current-generation LDMOS alternatives for improved performance and availability.