BFR91 NPN RF Transistor Technical Summary

Overview

The BFR91 is a high-performance NPN silicon RF transistor designed for applications requiring high power gain and low noise figure. Packaged in a TO-50 metal can, this device offers excellent high-frequency characteristics with a high transition frequency, making it suitable for various RF amplification stages. Its robust construction and reliable performance make it a preferred choice for communication systems, broadcast equipment, and other RF applications.

Features

• High Power Gain: Delivers superior signal amplification capabilities for RF applications
• Low Noise Figure: Excellent signal-to-noise ratio performance for sensitive receiver circuits
• High Transition Frequency (f_T): Enables operation at high frequencies with good gain characteristics
• TO-50 Metal Package: Provides excellent thermal performance and mechanical durability
• Optimized for RF Applications: Designed specifically for radio frequency operation

Applications

The BFR91 is ideally suited for a wide range of RF applications, including:

• RF amplifiers in communication systems
• VHF/UHF transmitter and receiver stages
• Oscillator circuits
• Signal processing equipment
• Broadcast equipment
• Radio base stations
• Test and measurement instruments
• Military and aerospace communication systems

Electrical Characteristics

Absolute Maximum Ratings

Stresses beyond these ratings may cause permanent damage to the device.

• Collector-Base Voltage (V_CBO): 20 V
• Collector-Emitter Voltage (V_CEO): 12 V
• Emitter-Base Voltage (V_EBO): 2 V
• Collector Current (I_C): 50 mA
• Total Power Dissipation (P_tot): 300 mW (at T_amb = 25°C)
• Operating Junction Temperature (T_j): +150°C
• Storage Temperature Range (T_stg): -65°C to +150°C

Typical Electrical Characteristics

(T_amb = 25°C unless otherwise specified)

• DC Current Gain (h_FE): 40-250 (at I_C = 10 mA, V_CE = 5 V)
• Transition Frequency (f_T): 5 GHz (typical)
• Noise Figure (NF): 1.5 dB (typical at 1 GHz)
• Power Gain (G_p): 15 dB (typical at 1 GHz)
• Collector-Emitter Saturation Voltage (V_CE(sat)): 0.3 V (max at I_C = 10 mA, I_B = 1 mA)
• Base-Emitter Voltage (V_BE): 0.7 V (typical at I_C = 10 mA)

Package Information

TO-50 Metal Can Package

• Package Type: Hermetically sealed metal can
• Terminal Configuration:
  • Pin 1: Collector
  • Pin 2: Base
  • Pin 3: Emitter
• Dimensions: 5.08 mm diameter × 4.83 mm height (excluding leads)
• Lead Material: Kovar with gold plating
• Weight: Approximately 0.5 grams
• Mounting: Through-hole with recommended hole diameter of 1.0 mm
• Marking: Device identification code laser marked on top surface

Thermal Characteristics

• Thermal Resistance, Junction to Case (R_thJC): 83.3°C/W
• Thermal Resistance, Junction to Ambient (R_thJA): 250°C/W (without heatsink)

Reliability Data

• MIL-STD-750 Test Method 1036: Pass
• MIL-STD-750 Test Method 1021: Pass
• ESD Sensitivity: Class 1 (Human Body Model)
• Moisture Sensitivity Level (MSL): Level 1 (Unlimited floor life at ≤30°C/85% RH)

Handling and Storage Recommendations

• Store in original packaging or antistatic containers
• Maintain storage temperature between -65°C and +150°C
• Use proper ESD precautions during handling and installation
• Avoid mechanical stress on leads during assembly
• Clean only with approved solvents and methods

Soldering Information

• Wave Soldering: Not recommended due to package type
• Hand Soldering: Maximum temperature 300°C for 10 seconds maximum
• Reflow Soldering: Not recommended for TO-50 package

Design Considerations

When designing with the BFR91 transistor, consider the following:

• Ensure proper impedance matching for optimal RF performance
• Implement appropriate biasing networks for stable operation
• Consider thermal management for high-power applications
• Use RF layout best practices (short leads, proper grounding)
• Implement proper decoupling for power supply lines