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This section provides an overview for photocouplers as well as their applications and principles. Also, please take a look at the list of 6 photocoupler manufacturers and their company rankings. Here are the top-ranked photocoupler companies as of December, 2024: 1.Felite Resin Technology, 2.Richardson RFPD, 3.KODENSHI CORP..
Table of Contents
A photocoupler is a device that can transmit a signal from an input side to an output side while electrically isolating the circuits on the input side and the output side.
It is also called an opto-isolator or optical isolator. In a photocoupler, the input electrical signal is converted to an optical signal using a light emitter, and the optical signal is converted back to an electrical signal using a light receiving element to make an output signal.
This means that signals can be transmitted even when the circuit on the output side is not electrically connected to the circuit on the input side. This high level of insulation is the primary reason for using photocouplers. Another feature is its relatively long life as a means of signal transmission.
Photocouplers are used in devices that require high reliability due to their features of insulation and long life. Examples include medical electronic equipment.
In audio and communication equipment, where low noise is required, photocouplers are used to transmit signals from digital circuits to analog circuits, preventing noise from entering the analog circuits.
Photocouplers are also used in devices that drive motors. Recently, inverter-controlled motors are widely used, but noise generation is inevitable in rotation speed control. Since this noise can get into the equipment and cause malfunctions, signals are transmitted through photocouplers to block the noise from the motors.
In addition, photocouplers are also used to transmit signals between devices that operate on independent power supplies. Especially when connected to floating devices, there is a risk of electric shock, but if connected via photocouplers, safety can be ensured because the devices are insulated from floating devices.
As mentioned above, a photocoupler is a unit that combines a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor, and encloses these elements in a package that blocks light from the outside. The light emitting and light receiving elements are mounted close together. When the light emitting element is turned on, the light receiving element changes from the OFF state to the ON state, which is the principle of signal transmission by photocouplers.
The device outputting the signal connects to the input terminal of the photocoupler and turns the light emitting element on and off. The device receiving the signal is connected to the photocoupler's output terminal via a pull-up resistor of a few kΩ to the power supply. With this configuration, the output terminal of the photocoupler is equal to the power supply voltage when the light-emitting element is off, and is about 0.1 V~0.3 while the light-emitting element is on.
That is, pulses appear in response to the turning on/off of the light-emitting element by the device outputting the signal, and the device on the receiving side receives these pulses and proceeds with signal processing. In this way, the photocoupler couples the input and output circuits via light, but there is no electrical connection between them because they are insulated.
There are various types of photocouplers, depending on the application. Typical elements are listed below.
This is the basic configuration of photocouplers. It is still the most widely used photocoupler in the market due to its low price and high versatility. There are products with various features such as high conversion efficiency, high withstand voltage, and low input drive. They have a wide range of functions, and their main applications are signal isolation, feedback detection, and isolated switches.
Photocouplers are integrated circuits with a light-receiving element to achieve high speed and specific functions. IC-output photocouplers can be further classified into the following three categories:
Used as isolated switches to directly control AC loads such as motors and solenoids directly connected to 100 V or 200 V commercial power supplies used in homes, offices, factories, and other locations. Using a triac with high element breakdown voltage, it is possible to control AC loads ON/OFF with a minute current of about 10 or more mA while electrically insulating them.
The element by itself can control only about 100mA of AC current, but by using it as a driver for an external triac, it can control AC currents up to several A.
The MOSFET output photocoupler has two MOSFETs connected at the source common in the output stage and has the same functionality as a mechanical relay. This is a feature of photocouplers.
The current transfer ratio (CRT) is a characteristic parameter of photocouplers. The current transfer factor is the ratio of the output current (IC) to the input forward current (IF) and is equivalent to the DC current amplification factor (hFE) of a transistor.
These factors must be taken into account when designing circuits. In other words, if the current transfer coefficient fluctuates due to environmental changes or over time, the output current will change, which may cause the circuit to malfunction. Therefore, it is important to examine the IF value, pull-up resistor resistance value, etc. to ensure that fluctuations in signal level do not affect the output current.
In addition, if a photocoupler is used for a long period of time, the current transfer coefficient will gradually decrease, and sufficient signal output will no longer be obtained. The main cause of the decrease in the current transfer coefficient is the deterioration of the LEDs, which results in a decrease in luminous efficiency.
The life expectancy of photocouplers is clearly stated in the device manufacturer's literature, so it is necessary to determine the model and conditions of use with reference to this information.
*Including some distributors, etc.
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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.
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.
Established in 1972, Felite™ Resin Technology is a leading global manufacturer of high-quality ion exchange resins. Its primary objective is to become the industry’s most reliable and competitive supplier, offering a complete range of ion exchange media to meet the ever-evolving needs of our customers. Over the past five decades, Felite Resin Technology has done a good job of supplying essential ion exchange resin media for water treatment systems all across the world. This company combines first-rate customer service with affordable, high-quality Chinese-made components. Felite Resin Technology has developed hundreds of resin models to cater to various applications, including industrial deionization, water softening, metals removal, juice purification, resource recovery, pollution control, hydrometallurgy, and municipal water treatment. This company removes the guesswork from maintaining your valuable water treatment equipment by providing you with transparent communication, superior support, and high-quality ion exchange media.
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.
Kodenshi Corp. is an ISO 14001 and IATF 16949-certified manufacturer of optical devices that was established in 1972 in Kyoto, Japan. The company’s product lineup includes photointerrupters for sensing motion or positioning, photodiodes for converting light into electrical currents, and phototransistors for amplifying currents generated by photodiodes. It also offers encoders for converting motion into digital signals, and photo couplers for noise reduction or signal isolation. The company’s products are commonly used within the private security and transportation sectors, and have additional applications in the automotive industry.
Richardson RFPD, based in Geneva, Illinois, is an electronic component distributor that became a subsidiary of Arrow Electronics in 2011. The company stocks products such as antennas, power supplies, and ICs, and its engineering team brings together over 600 years of combined design experience in IoT product development, wireless, and RF, making it competent from conception to production. The company is ISO 9001 certified and has three international distribution hubs in Asia, Europe, and North America. It sells products from several brands, including Advanced Thermal Solutions, Empower RF Systems Inc., and Carlisle Interconnect Technologies.
Ranking as of December 2024
Derivation Method| Rank | Company | Click Share |
|---|---|---|
| 1 | Felite Resin Technology |
52.6%
|
| 2 | Richardson RFPD |
15.8%
|
| 3 | KODENSHI CORP. |
15.8%
|
| 4 | Vishay Intertechnology, Inc., |
5.3%
|
| 5 | Renesas Electronics Corporation. |
5.3%
|
| 6 | Toshiba Electronic Devices & Storage |
5.3%
|
Derivation Method
The ranking is calculated based on the click share within the photocoupler page as of December 2024. Click share is defined as the total number of clicks for all companies during the period divided by the number of clicks for each company.Number of Employees
Newly Established Company
Company with a History
*Including some distributors, etc.
*Including some distributors, etc.
| Country | Number of Companies | Share (%) |
|---|---|---|
|
Japan
|
2 | 50.0% |
|
United States of America
|
1 | 25.0% |
|
China
|
1 | 25.0% |
Seiwa Co., Ltd.
40+ people viewing
A general-purpose transistor output type photocoupler.
Seiwa Co., Ltd.
40+ people viewing
Last viewed: 10 hours ago
This is a photocoupler with Darlington output.
Seiwa Co., Ltd.
50+ people viewing
Last viewed: 3 hours ago
This is a photocoupler with phototriac output.
Seiwa Co., Ltd.
40+ people viewing
Last viewed: 1 day ago
A general-purpose transistor output type photocoupler.
Seiwa Co., Ltd.
50+ people viewing
Last viewed: 1 day ago
This is a solid state relay type PhotoMOS. We have a lineup of products with breakdown voltages of 60V to 600V output.
Seiwa Co., Ltd.
70+ people viewing
Last viewed: 1 day ago
A photocoupler that can be used as an IGBT gate driver. Our lineup includes products capable of outputting 0.6A to 4.0A.
Nimatsu Electric Co., Ltd.
70+ people viewing
Last viewed: 9 hours ago
Letex Technology is a manufacturer of Photo DMOS-FET relays, optocouplers, and other Photo related products, founded in Taiwan in 2001. Obtained IS...
Optoscience Co., Ltd.
30+ people viewing
Last viewed: 9 hours ago
■Summary ・200W inline optical isolator @1,064nm ideal for fiber laser and measurement applications. -Features low insertion loss, high isolation, ...
Optoscience Co., Ltd.
10+ people viewing
Last viewed: 13 hours ago
■Summary Highest quality optical isolator designed for high power pulsed lasers. There are two design versions to suit 100W and 200W lasers. Backe...
Optoscience Co., Ltd.
10+ people viewing
Last viewed: 19 hours ago
■Summary -Protects your high power laser from back reflections of different wavelengths and beam diameters. ・Suitable for various applications wit...
Optoscience Co., Ltd.
20+ people viewing
Last viewed: 20 minutes ago
■Summary ・We provide solutions for fiber lasers that require operation in a wide temperature range. -SeasonBeam™ features a patented design that p...
Optoscience Co., Ltd.
20+ people viewing
Last viewed: 12 hours ago
■Summary This is an isolator designed for industrial fiber lasers. The new design supports an average laser power of 500W at an affordable price. ...
TOPTICA Photonics AG
540+ people viewing
Last viewed: 25 minutes ago
The stability of the laser, which is characterized by narrow line width and long -losing interference distance, can protect watt -class lasers and ...
10 models listed
TOPTICA Photonics AG
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The stability of the laser, which is characterized by narrow line width and long -losing interference distance, can protect watt -class lasers and ...
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Keisei Co., Ltd.
10+ people viewing
■Features ・Features: JEDEC compatible / analog output compatible ・Applications: For communication interface / for PLC / for measuring instruments...
Towa Electronics Co., Ltd.
10+ people viewing
Last viewed: 6 hours ago
A photocoupler suitable for IGBT/MOSFET gate drive. We have a wide lineup of products, including types with built-in overcurrent protection functio...
Towa Electronics Co., Ltd.
10+ people viewing
Last viewed: 19 hours ago
A photovolt output photocoupler is an element that receives LED light with a photodiode array on the receiving side and extracts the output voltage...
Towa Electronics Co., Ltd.
10+ people viewing
Last viewed: 19 hours ago
A photocoupler compatible with power supply voltages of 5V and 15V, ideal for isolated interfaces of IPM (Intelligent Power Module). The output cir...
Towa Electronics Co., Ltd.
10+ people viewing
Last viewed: 12 hours ago
We have a lineup of products that support a variety of communication standards, from medium-low speed communications such as RS-232 to high-speed c...
Towa Electronics Co., Ltd.
Last viewed: 19 hours ago
A photocoupler for automotive applications that complies with IATF16949. We have a wide lineup of products with various output types. These product...
Towa Electronics Co., Ltd.
10+ people viewing
Last viewed: 12 hours ago
Our isolation amplifier is an optically coupled isolation amplifier equipped with a high-precision ΔΣAD conversion circuit on the input side. Mainl...
Würth Elektronik
30+ people viewing
Last viewed: 2 hours ago
■Features ・High insulation voltage ・Good internal isolation stability ・Stable CTR with full operation ・Various CTR binning options available ・...
Fiblab Co., Ltd.
320+ people viewing
Last viewed: 1 day ago
■ Characteristics ・ It is an built -in light isolator with PBS and phase board integrated. ・ We will manufacture according to the specified wavel...
Konoshima Chemical Co.,Ltd.
50+ people viewing
Last viewed: 1 day ago
■Transmits light in only one direction and eliminates reflected light It is used as a unit integrated with optical fiber, etc. The TGG (Tb3Ga5O12) ...
Toho Technology Co., Ltd.
30+ people viewing
Last viewed: 9 hours ago
■Features - A photocoupler isolation type interface unit that can cut out external noise. ・The lineup includes the PXWP series equipped with a scr...
