ample-chip ample-chip
RFQ
BOM

Transistors - Bipolar (BJT) - RF

Image Part Number Description / PDF Quantity Rfq
BLT81,115

BLT81,115

NXP Semiconductors

RF TRANS NPN 9.5V 900MHZ SOT223

0
KSC1393RTA

KSC1393RTA

Sanyo Semiconductor/ON Semiconductor

RF TRANS NPN 30V 700MHZ TO92-3

0
START499D

START499D

STMicroelectronics

RF TRANS NPN 4.5V SOT89

0
2SC5509-A

2SC5509-A

CEL (California Eastern Laboratories)

RF TRANS NPN 3.3V 15GHZ SOT343F

0
NE68033-T1B-A

NE68033-T1B-A

CEL (California Eastern Laboratories)

RF TRANS NPN 10V 10GHZ SOT23

0
NE664M04-A

NE664M04-A

CEL (California Eastern Laboratories)

RF TRANS NPN 5V 20GHZ SOT343F

0
BGB 540 E6327

BGB 540 E6327

IR (Infineon Technologies)

RF TRANS NPN 3.5V SOT343-4

0
2SC5010-A

2SC5010-A

CEL (California Eastern Laboratories)

RF TRANS NPN 6V 12GHZ SOT523

0
DMC506E20R

DMC506E20R

Panasonic

RF TRANS 2 NPN 20V 650MHZ SOT363

0
AT-32033-TR1

AT-32033-TR1

Broadcom

RF TRANS NPN 5.5V SOT23

0
SD1274-01

SD1274-01

STMicroelectronics

RF TRANS NPN 16V M113

0
BLT80,115

BLT80,115

NXP Semiconductors

RF TRANS NPN 10V 900MHZ SOT223

0
AT-30511-TR2G

AT-30511-TR2G

Broadcom

RF TRANS NPN 5.5V SOT143

0
FMMT918TA

FMMT918TA

Zetex Semiconductors (Diodes Inc.)

RF TRANS NPN 15V 600MHZ SOT23-3

0
2SC4095-A

2SC4095-A

CEL (California Eastern Laboratories)

RF TRANS NPN 10V 10GHZ SOT143

0
KSC1674RTA

KSC1674RTA

Sanyo Semiconductor/ON Semiconductor

RF TRANS NPN 20V 600MHZ TO92-3

0
UPA814T-A

UPA814T-A

CEL (California Eastern Laboratories)

RF TRANS 2 NPN 6V 9GHZ 6SO

0
UPA806T-T1

UPA806T-T1

CEL (California Eastern Laboratories)

RF TRANS 2 NPN 6V 12GHZ 6SO

0
BFG135,115

BFG135,115

NXP Semiconductors

RF TRANS NPN 15V 7GHZ SOT223

0
NE85634-T1

NE85634-T1

CEL (California Eastern Laboratories)

RF TRANS NPN 12V 6.5GHZ SOT89

0

Transistors - Bipolar (BJT) - RF

1. Overview

Radio Frequency Bipolar Junction Transistors (RF BJTs) are three-layer semiconductor devices optimized for amplification and switching in high-frequency applications (typically >100 MHz). These transistors maintain stable performance in microwave and ultra-high frequency (UHF) ranges, characterized by high current gain-bandwidth product (fT), low noise figures, and fast switching capabilities. Their importance in modern technology spans wireless communication infrastructure, radar systems, and RF test equipment, enabling efficient signal transmission and reception in 5G networks, satellite communications, and IoT devices.

2. Main Types & Functional Classification

TypeFunctional FeaturesApplication Examples
NPN RF BJTHigh electron mobility, optimized for low-noise amplification5G base station LNAs, GPS receivers
PNP RF BJTComplementary design for power amplificationRF power modules, automotive radar
RF Darlington PairHigh (current gain), cascaded amplificationAntenna drivers, industrial RF heaters
Heterojunction Bipolar Transistor (HBT)Compound semiconductor materials (SiGe/GaAs), ultra-high fTOptical communication transceivers, mmWave systems

3. Structure & Composition

Typical RF BJT structure includes:

  • Material: Silicon (Si), Silicon-Germanium (SiGe), Gallium Arsenide (GaAs)
  • Layer Architecture: Emitter (high doping), Base (thin layer), Collector (graded doping)
  • Package Types: Surface-mount (SOT-89, SOT-343), Through-hole (TO-18, TO-92)
  • Metallization: Gold/aluminum contacts for reduced parasitic resistance

Advanced designs incorporate air-bridge structures to minimize parasitic capacitance and epitaxial layers for improved frequency response.

4. Key Technical Parameters

ParameterDescriptionTypical Range
fT (Transition Frequency)Current gain cutoff frequency1 GHz - 100 GHz
GUM (Max. Available Gain)Power gain at optimal impedance10 dB - 30 dB
Pout (Output Power)RMS power capability0.1 W - 500 W
NF (Noise Figure)Signal-to-noise degradation0.3 dB - 5 dB
VCE0 (Breakdown Voltage)Collector-emitter withstand voltage5 V - 80 V
(Junction Temperature)Thermal stability limit150 C - 200 C

5. Application Fields

  • Telecommunications: 5G massive MIMO amplifiers, fiber optic transceivers
  • Defense: Phased array radar systems, electronic warfare jammers
  • Test & Measurement: RF signal generators, spectrum analyzers
  • Consumer Electronics: Bluetooth LE modules, Wi-Fi 6E front-ends
  • Industrial: Plasma generators, RFID readers

6. Leading Manufacturers & Products

ManufacturerRepresentative ProductKey Specifications
Infineon TechnologiesBFP740FfT=50 GHz, NF=0.8 dB, Pout=18 dBm
STMicroelectronicsSTAG21412.7 GHz dual-stage amplifier, 32 dB gain
Skyworks SolutionsASK240110.05-6 GHz, 50 W GaAs power transistor
ON SemiconductorMRF151G125 W, 880 MHz, 40% efficiency

7. Selection Guidelines

Key considerations:

  1. Match fT to application frequency with 20% margin
  2. Verify load-line requirements for power applications
  3. Select appropriate package for thermal dissipation (e.g., TO-220 for >50 W)
  4. Derate VCE0 by 30% in high-temperature environments
  5. Consider integrated solutions (RFICs) for complex impedance matching

8. Industry Trends

Future development directions:

  • Transition to SiGe BiCMOS technology for 100+ GHz applications
  • Integration with GaN-on-SiC substrates for hybrid power amplifiers
  • Development of 5G NR direct-conversion transmitters using HBT arrays
  • Advancements in wafer-level packaging (WLP) for mmWave 5G devices
  • Adoption of AI-driven parameter optimization in production testing
RFQ BOM Call Skype Email
Top