A diode is an electronic device made of semiconductor materials such as silicon, selenium, and germanium. A diode has two electrodes: the positive electrode (also known as the anode) and the negative electrode (also known as the cathode). When a forward voltage is applied between the two electrodes of the diode, the diode conducts; when a reverse voltage is applied, the diode blocks the current flow. The conduction and blocking of the diode are equivalent to the connection and disconnection of a switch.

A diode has a unidirectional conductivity, with the current flowing from the anode to the cathode when it conducts.

Here are the latest rankings of diode brands:

1. NICHIA:
NICHIA, founded in Japan in 1956, is dedicated to the development, manufacturing, and sales of precision chemicals centered around phosphors and inorganic fluorescent materials. The company is engaged in research and development of LED displays and high-power LED lighting.

2. ams OSRAM:
ams OSRAM is a group formed by the merger of ams Semiconductor and OSRAM, establishing itself as a global leader in optical solutions by providing sensor and lighting technology in transformative cutting-edge fields.

3. LUMILEDS:
Lumileds is a well-known provider of innovative lighting solutions globally, authorized to use the Philips brand for its automotive lighting and accessory product portfolio and now a subsidiary of the American Apollo Global Management. The company is mainly engaged in the design and development of high-power LED components and LED chips, enjoying a good reputation in the fields of automotive, mobile, IoT, and lighting.

4. Seoul Semiconductor:
Seoul Semiconductor, founded in South Korea in 1992, is a well-known LED lighting equipment manufacturer, focusing on providing international LED professional enterprises from IT/automotive lighting to general lighting fields.

5. Samsung LED:
Samsung Electronics' subsidiary dedicated to the LED industry provides core component products for LED lighting systems, including various modules for displays, mobile devices, automobiles, and smart lighting solutions, with LED patent technology covering EPI, chips, packaging, phosphors, modules, and drivers.

6. MLS Lighting:
MLS was established in 1997 and listed on the Shenzhen Stock Exchange in China in 2015. It is a well-known LED packaging and LED application product supplier in China, a comprehensive optoelectronic new technology industry company integrating research and development, production, and sales.

7. EVERLIGHT:
EVERLIGHT, founded in Taiwan in 1983, is a well-known LED lamp brand, focusing on the LED industry, providing complete and multi-faceted solutions for various LED applications.

8. LITEON:
LITEON, founded in Taiwan in 1975, is an electronic company, a manufacturer of optoelectronic components and electronic key modules, focusing on core optoelectronic components and electronic key components, engaged in R&D and production of optoelectronic products, information technology, storage devices, and other products.

9. Nationstar Optoelectronics:
Nationstar Optoelectronics, founded in 1969, is a leading LED packaging company in China, with a dominant market share in the display devices/white light devices, specializing in R&D, production, and sales of LED and LED application products.

10. HONGLI Zhihui:
HONGLI, founded in 2004, is a modern enterprise in China specializing in the production of lighting devices and lighting modules, with main business segments including LED packaging and LED automotive lighting, and has established production bases in Guangzhou, Nanchang, Dongguan, and Danyang.

It is important to note that when choosing a diode brand, it is necessary to select based on specific application scenarios and requirements.