What Is a F Coupler?

A photocoupler is an electrical-optical-electrical conversion device that transmits electrical signals using light as a medium. It consists of a light source and a light receiver. The light-emitting source and the light-receiver are assembled in the same closed casing, and are separated from each other by a transparent insulator. The light-emitting source pins are input terminals, and the light-receiver pins are output terminals. Common light-emitting sources are light-emitting diodes, and the light-receivers are photodiodes, phototransistors, and so on.

Testing of Photocouplers

1.Use

As a terminal isolation component in long-line information transmission, the signal-to-noise ratio can be greatly improved. Therefore, it has been widely used in various circuits. At present, it has become one of the most diverse and widely used optoelectronic devices.

Photocoupler application

Because there are many types and types of optocouplers,

When designing the optocoupler optical isolation circuit, the model and parameters of the optocoupler must be correctly selected. The selection principles are as follows:

(1) Since the photocoupler is a signal unidirectional transmission device, and the data transmission in the circuit is bidirectional, the size of the circuit board must be certain. Combined with the actual requirements of circuit design, it is necessary to choose a single chip integrated multi-channel optocoupler . ^[1]

First, reverse voltage must be applied;

Second, the phototransistor case must be kept clean. ^[1]

Although the Japanese optocoupler market is not large, it is increasing at an annual growth rate of 40%. The main reason is that each program controller uses 20 to 30 or more optocouplers. Now, optocouplers have shown a clear trend toward large capacity and high speed. The photocouplers produced by the United States and Japan are mainly composed of infrared light emitting diodes and photosensitive device tubes, which account for about 60% of all photocouplers produced by the United States and Japan. Because this type of device not only has high current transmission efficiency (generally 7-30%), but also has a fast response speed (2-5s), it can meet the requirements of most applications. ^[1]

Photocouplers are widely used in many electronic devices. With the rapid development of digital communication technology and the application of automatic control components such as optical isolators and solid-state relays in the machinery industry, especially the application and promotion of microprocessors in various fields (sometimes the amount of a microcomputer can reach (A dozen or even hundreds) and the gradual improvement of product performance, the application market of optocouplers will gradually expand, at the same time, its social and economic benefits will be very significant. In the future, optocouplers will develop in the direction of high speed, high performance, small size, and light weight. ^[1]