This section provides an overview for bipolar transistors as well as their applications and principles. Also, please take a look at the list of 13 bipolar transistor manufacturers and their company rankings. Here are the top-ranked bipolar transistor companies as of March, 2024: 1.Microsemi Corporation, 2.Infineon Technologies AG, 3.Sanken Electric Semiconductors.
A bipolar transistor is a three-terminal semiconductor device.
Also called a junction transistor, it consists of N-type and P-type semiconductors in a P-N-P or N-P-N junction structure. Unlike field effect transistors (FETs), which are unipolar transistors in which either holes or free electrons act as carriers, bipolar transistors are called bipolar because both holes and free electrons are involved in their operation.
The two main functions of bipolar transistors are amplification and switching.
In amplification circuits that turn minute signals into sufficiently large levels, bipolar transistors are more advantageous than unipolar transistors, especially when a high amplification factor is required. Bipolar transistors are also superior in operating at high frequencies.
For example, in power supply regulator circuits where switching noise with high-frequency components must be suppressed, there is a marked difference in noise rejection ratio and other characteristics between circuits using bipolar transistors and those using FETs.
Bipolar transistors are still used in small-lot production and high-frequency amplification circuits that are difficult to make into ICs, but because they are current-driven, they consume more power than unipolar transistors, which are voltage-driven. However, because they are current-driven, they consume more power than voltage-driven unipolar transistors.
On the other hand, switching circuits are used for ON/OFF control of current, but unipolar transistors are superior in terms of switching speed and miniaturization, so they are rarely used for this purpose.
Semiconductors can be classified into P-type and N-type semiconductors: P-type semiconductors are filled with holes, which are missing electrons; N-type semiconductors are filled with free electrons, which are in surplus.
Transistors are a combination of P- and N-type semiconductors. In the case of bipolar transistors, there are two types of transistors: one consisting of three regions: P-type, N-type, and P-type, and the other consisting of three regions: N-type, P-type, and N-type.
The former is called a PNP transistor and the latter an NPN transistor; the three regions are the emitter, base, and collector, each of which is connected to an electrode through which voltage is applied and a signal current flows. The base is characterized by being extremely thin.
The principle of operation of a bipolar transistor is explained using the example of an NPN-type transistor, which has an N-type semiconductor sandwiched between a P-type semiconductor.
With the emitter connected to the reference voltage (0V) and the collector connected to VCC (e.g. +5V), when a positive voltage is applied to the base and a base current Ib flows to the emitter, a current Ic of β × Ib flows from the collector to the emitter. This is the principle of amplification by a transistor, which is based on current amplification in bipolar transistors. β is called the current amplification factor and is usually around 100~200. In PNP transistors, the direction of the applied voltage and current is opposite, but the principle of amplification is the same.
In switching operation, a large base current Ib allows sufficient current to flow to the load connected to the collector. Also, if the base current is set to 0A, no current flows to the load. By flowing/not flowing the base current Ib, the current flowing to the load is turned ON/OFF and the switching operation is realized.
Type Names of Bipolar Transistors
Before 1993, the JIS standard stipulated how to name semiconductor components. Therefore, the application of a transistor can be determined to some extent from its type name. For Bipolar Transistors, the first three letters are as follows
The actual type name, for example, 2SA372Y, is composed of three letters followed by a number and an alphabet. The numbers start with 11 and consist of 2 to 4 digits, but they are assigned in the order of registration and have no meaning. The last alphabet means the rank classification of the amplification ratio.
This JIS standard was abolished in 1993 but has continued to be used in the standard "Type Names of Individual Semiconductor Devices" issued by the Japan Electronics and Information Technology Industries Association (JEITA), which succeeded it.
*Including some distributors, etc.
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Power Integrations, a manufacturer of power semiconductor solutions, was established in 1988 and is headquartered in San Jose, California. The company provides cutting-edge technologies for high-efficiency power conversion, serving industries such as electronics, consumer electronics, and industrial. The company also offers a range of services to its customers, including design support, application engineering, and product training. The company intends to help its customers design and implement efficient and dependable power solutions possible.
Vishay Intertechnology, Inc. (Vishay) was incorporated in 1962 and is headquartered in Malvern, Pennsylvania. The company serves the industrial, automotive, telecommunications, consumer products, and medical end markets and sells its products under numerous brand names inlcuding Siliconix, Draloric, Beyschlag, UltraSource, and Applied Thin-Film Products. The company manufactures and sells discrete semiconductors and passive electronic components in globally while operating in six market segments: MOSFETs, diodes, optoelectronic components, resistors, inductors, and capacitors.
Microsemi Corporation was founded in 1959 and is headquartered in Aliso Viejo, California. Microsemi is a subsidiary of Microchip Technology Incorporated. Microsemi is a provider of semiconductor and system solutions for aerospace, communications, data center, and industrial markets. A few of Microsemi’s product lines include high-performance and radiation-hardened analog mixed-signal integrated circuits, FPGAs, power management products, timing and synchronization devices, and RF solutions. Microsemi’s technological strengths are in connectivity, energy efficiency, miniaturization, power management, and security.
Diodes Incorporated is a supplier for the consumer electronics, computing, communications, industrial, and automotive markets. Diodes Incorporated designs, manufactures, and supplies application-specific standard products in the discrete, logic, analog, and mixed-signal semiconductor markets worldwide. It focuses on low pin count semiconductor devices. Diodes specializes in semiconductor products, such as MOSFET, TVS, and performance Schottky rectifiers, transient voltage suppressors and other devices. It also provides analog products, such as power management devices comprising AC-DC and DC-DC converters, signaling devices, CMOS devices, and analog switches. Diodes Incorporated was incorporated in 1959 and is headquartered in Plano, Texas.
Diotec Semiconductor AG is a German-based semiconductor manufacturer and supplier of diodes and rectifiers which was founded in 1973 and is headquartered in Heitersheim, Germany. They specialize in producing discrete semiconductors, both standard and customized, readily available for worldwide delivery. Their product portfolio includes diodes, rectifiers, protection devices (TVS/ESD), transistors, and regulators. These products are used in various applications such as in industrial, energy, mobility, lighting, and consumer electronics, contributing to power management, signal conditioning, and circuit protection in different electronic systems and devices.
Renesas Electronics Corporation was established in 2002 and is headquartered in Tokyo, Japan. Renesas is a global research, design, and manufacturer of semiconductors used in industries spanning automotive, consumer electronics, the internet of things, power & energy, and industrial sectors. Renesas manufactures both analog and digital products. Analog products include amplifiers, audio & video devices, data converters, PLC, and switches & multiplexers. Digital products include microcontrollers, memory components, sensors, wireless connectivity products, and others. Renesas also offers design resources such as kits, development tools, partner programs, and design tools.
Nexperia is based in the Netherlands and is a designer, manufacturer, and global supplier of semiconductors. Their stock includes Bipolar Transistors, Diodes, MOSFETs, GaN FETs, and various ICs that are used as basic components in electronic systems and devices and have multiple applications. These parts are supplied to the automotive, computing, power, and electronic industries as parts of a system or as essential tools for various gadgets and devices. They are also used by manufacturers of consumer appliances such as smartphones, batteries, aerial vehicles, fire detectors, and more.
Toshiba Electronic Devices & Storage Corporation is a division of Toshiba focusing on providing designs for end-product developers as well as semiconductor and drive equipment for automotive, industrial equipment, green energy, and consumer and personal electronic devices. Toshiba’s storage products include cloud-scale and enterprise-level products, and PC hard drives. Semiconductor products include Si Cower devices, MOSFETs, IGBTs, IEGTs, isolators, solid state relays, power management and intelligent power ICs, diodes, bipolar transistors, microcontrollers, automotive devices, ICs for wireless communication equipment, general purpose logic ICs, radio-frequency devices, sensors, and linear image sensors.
Infineon Technologies AG (Infineon) is headquartered in Neubiberg, Germany. Infineon designs, develops, manufactures, and markets semiconductors and related system solutions worldwide. Infineon’s automotive segment produces microcontrollers, discrete power semiconductors, IGBT modules, industrial microcontrollers, power and radar sensor ICs, SiC diodes, MOSFETs voltage regulators, comfort electronics, infotainment, powertrain, and security products. Industrial Power Control segment provides bare dies, discrete IGBTs, and driver ICs among other components. Power & Sensor Systems segment offers gas and pressure sensors, MEMS microphone chips, control ICs, and GaN power switches among others.
ST Micro Electronics is a global semiconductor company serving customers with innovations to have a positive impact on people's lives. Their product line is micro electronic systems, such as switches, controllers, sensors and drivers. The main selling point of ST Micro Electronics is its provision of sustainable products, and introducing their electronics to create a more sustainable world. The company, as well as providing the electronic devices, also provides software and support, ensuring that all fields are covered to provide a fully provide a supported and strong relationship with their customer base. ST Micro Electronics believe that technology plays a key role in helping to solve environmental and social challenges, which is why their semiconductor technologies start with their employees, their customers and partners.
Taiwan Semiconductor, established in 1979 in Taiwan, is a manufacturer and distributor of integrated circuits and wafer semiconductor devices for commercial and industrial customers worldwide. The company's product line includes discrete power rectifiers, power transistors, LED driver ICs, analog ICs, and ESD protection devices. Taiwan Semiconductor has production facilities in China and Taiwan that are compliant with automotive and environmental standards, including IATF 16949, ISO 9001, and ISO 14001. Taiwan Semiconductor is also a member of the ECIA and the PSMA.
Sanken Electric Semiconductors, established in 1946 and headquartered in Saitama-ken, Japan, is a semiconductor manufacturer specializing in power semiconductors. The company serves in the power electronics field offering a wide range of products, including discrete semiconductors, IPMs, power supply ICs, and digitally controlled ICs. The technologies applied by their company enable the development of energy-saving products for global markets. Their semiconductors can be found in various electric equipment and devices, from home appliances to automobiles and industrial equipment. They have about 1,000 employees with 10 distributors and vendors across North America, Europe, and Asia.
ROHM Semiconductor was incorporated in 1940 and is headquartered in Kyoto, Japan. ROHM manufactures and sells electronic components worldwide. ROHM operates through the segments ICs, discrete semiconductor devices, and modules. ROHM provides ICs comprising memory, amplifiers and linear, power management, clocks and timers, switches and multiplexers, logic, data converters, sensors and MEMS, display drivers, motor/actuator drivers, interfaces, communication and speech synthesis LSI, audio and video, and microcontrollers. ROHM also offers discrete semiconductor products include MOSFETs, bipolar transistors, and diodes; power devices, including power transistors and diodes, SiC power devices, IGBT, and IPM; passive devices, such as resistors, and conductive polymer and tantalum capacitors; and various modules among others.
*Including some distributors, etc.
*Including some distributors, etc.
|Number of Companies
|United States of America