Transistors - Bipolar (BJT)

Transistors - Bipolar (BJT) - Single

Part Number	Description / PDF	Quantity
2SA2060(TE12L,F) Toshiba Electronic Devices and Storage Corporation	TRANS PNP 50V 2A SC-62	0
2SA2097(TE16L1,NQ) Toshiba Electronic Devices and Storage Corporation	TRANS PNP 50V 5A SC-62	0
2SA1955FVBTPL3Z Toshiba Electronic Devices and Storage Corporation	TRANS PNP 12V 0.4A VESM	10780
2SC6026MFVGR,L3F Toshiba Electronic Devices and Storage Corporation	TRANS NPN 50V 0.15A VESM	49
TTC1949-Y,LF Toshiba Electronic Devices and Storage Corporation	NPN TRANSISTOR VCEO50V IC0.5A HF	5995
2SC6100,LF Toshiba Electronic Devices and Storage Corporation	NPN TRANSISTOR VCEO50V IC2.5A HF	0
2SC3325-Y,LF Toshiba Electronic Devices and Storage Corporation	TRANS NPN 50V 0.5A S-MINI	7382
2SA1586-Y,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 50V 0.15A USM	43
2SB906-Y(TE16L1,NQ Toshiba Electronic Devices and Storage Corporation	TRANS PNP 60V 3A PW-MOLD	1814
2SA1588-Y,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 30V 0.5A USM	4069
2SA1298-Y,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 25V 0.8A S-MINI	2974
2SA1312-BL(TE85L,F Toshiba Electronic Devices and Storage Corporation	TRANS PNP 120V 0.1A S-MINI	4242
2SA1587-GR,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 120V 0.1A USM	36452
2SA2195,LF Toshiba Electronic Devices and Storage Corporation	PNP TRANSISTOR VCEO-50V IC-1.7A	8990
TBC847B,LM Toshiba Electronic Devices and Storage Corporation	X34 PB-F SOT-23 TRANSISTOR FOR L	7846
2SA1832-Y,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 50V 0.15A SSM	0
2SA1163-GR,LF Toshiba Electronic Devices and Storage Corporation	TRANS PNP 120V 0.1A SMINI	19841
2SC6135,LF Toshiba Electronic Devices and Storage Corporation	NPN TRANSISTOR VCEO50V IC1A HFE4	91
TTC004B,Q Toshiba Electronic Devices and Storage Corporation	TRANS NPN 160V 1.5A TO126N	6002
2SC4738-GR,LF Toshiba Electronic Devices and Storage Corporation	TRANS NPN 50V 0.15A SSM	2874

Transistors - Bipolar (BJT) - Single

1. Overview

Bipolar Junction Transistors (BJTs) are three-terminal semiconductor devices that use both electron and hole charge carriers. They form the foundation of analog electronics through their ability to amplify signals and control current flow. BJTs remain critical in modern electronics for applications ranging from audio amplifiers to power management circuits, offering superior linearity and robustness in switching operations.

2. Main Types & Functional Classification

Type	Functional Characteristics	Application Examples
NPN Transistor	Majority carriers: electrons. Requires positive base current for conduction.	Low-noise amplifiers, digital logic circuits
PNP Transistor	Majority carriers: holes. Conducts with negative base current.	Power supply circuits, motor controllers
High-Frequency BJT	Optimized for RF/microwave signal amplification (f_T > 100 MHz)	Wireless communication systems, radar
Power BJT	High current/voltage ratings (I_C > 1A, V_CE > 50V)	Switch-mode power supplies, motor drives

3. Structure & Composition

BJTs consist of three doped semiconductor regions forming two p-n junctions:

Emitter: Heavily doped region emitting charge carriers
Base: Thin, lightly doped middle region controlling carrier flow
Collector: Moderately doped region collecting carriers

Manufactured using silicon (common) or germanium (historic) with planar processing technology. The structure forms either NPN (n-type emitter/base/collector) or PNP configuration, with metal contacts for external connections.

4. Key Technical Specifications

Parameter	Description	Importance
Current Gain (h_FE)	Ratio of collector to base current (10-1000)	Determines amplification capability
Transition Frequency (f_T)	Frequency at which current gain drops to 1	Limits high-frequency performance
Max Collector Current (I_Cmax)	Maximum allowable continuous collector current	Defines power handling capability
Breakdown Voltage (V_CEO)	Max voltage between collector and emitter	Prevents device failure under stress
Saturation Voltage (V_CEsat)	Voltage drop in fully conducting state	Affects power efficiency in switching

5. Application Areas

Consumer Electronics: Audio amplifiers, LED drivers
Automotive: Engine control units, electric vehicle inverters
Industrial: PLCs, motor controllers
Telecommunications: RF power amplifiers, fiber optic transceivers
Aerospace: Avionics systems, satellite transponders

6. Leading Manufacturers & Products

Manufacturer	Product Series	Key Specifications	Typical Use
ON Semiconductor	2N3904	hFE: 100-300, fT: 300 MHz	General-purpose switching
Infineon	BC547	VCEO: 50V, ICmax: 100mA	Analog signal amplification
STMicroelectronics	2SD2656	ICmax: 15A, VCEO: 80V	Power inverter applications
Diodes Inc.	BFR93A	fT: 10 GHz, Noise Figure: 2dB	High-frequency front-end amplifiers

7. Selection Guidelines

Determine operating frequency: Select fT > 3 target frequency
Power requirements: Ensure Icmax and VCEO exceed circuit requirements by 20%
Thermal considerations: Calculate power dissipation (P=V_CE I_C)
Package type: TO-92 for low power, TO-220 for high-power applications
Environmental factors: Consider temperature ratings for industrial/military use

8. Industry Trends

Future developments include:

High-frequency BJTs operating beyond 100 GHz for 6G communication
Integrated BJT-MOSFET hybrid devices (BiCMOS) for mixed-signal applications
Wide-bandgap materials (SiC/GaN) for higher power density
Miniaturization through chip-scale packaging
Improved thermal management solutions for automotive applications