China's diode markets diverge across rectification, protection and optoelectronics

China's diode industry connects several markets with very different economics. A bridge rectifier in a charger, a protection device beside an automotive interface, an LED chip and a laser inside an optical module do not face the same customers, processes or pricing conditions. Describing the industry through a single divide between domestic low-end supply and imported high-end products misses much of the current competition.

The 2026 interim disclosures show the differences clearly. Some businesses are shipping more while prices constrain profitability. Others, with revenue below RMB 1 billion, are earning much higher margins as their application and product mix changes. For international buyers and industry observers, the useful approach is to examine adoption and manufacturing economics within each product market.

Market boundaries change the meaning of scale and domestic participation

Power diodes include conventional rectifiers, Schottky and fast-recovery devices used in rectification, freewheeling and conversion. Bridges combine multiple diodes into a device or module, while photovoltaic bypass is another important power application.

The scope extends beyond power conversion. Zener and small-signal switching diodes support biasing, limiting and signal processing. TVS and diode-based ESD devices protect against surges and electrostatic discharge. RF PIN, varactor, step-recovery and Schottky detection or mixing devices serve circuits sensitive to frequency, parasitics and packaging.

Optoelectronics adds visible, infrared and ultraviolet LEDs; laser diodes, including vertical-cavity surface-emitting lasers, or VCSELs; and detectors such as PIN photodiodes and avalanche photodiodes, or APDs. Single-photon avalanche diodes and SiPM arrays extend this scope into weak-light and single-photon detection.

Figure 1. Functional map of diode categories. Categories can overlap and their revenues cannot simply be added. RF PIN diodes and PIN photodetectors perform different functions.

These boundaries matter for market sizing. MOSFETs and IGBTs belong to the wider power-semiconductor industry, and common GaN power transistors are not diodes. Optical-device statistics can mix chips, packaged components and modules. Adding LED chip sales to sales of packages using those chips would count part of the same industrial value twice. Solar cells and OLED panels also have separate industry statistics and are outside this discussion of discrete diode markets.

This article therefore focuses on mainland Chinese suppliers and uses identifiable applications, product businesses and financial scopes. It does not construct a purportedly complete total for China's diode market. Progress in conventional rectifiers cannot stand in for domestic participation in automotive protection, RF devices or high-speed photodetection.

Automotive electrification changes demand at specific circuit positions

Data published by China's Ministry of Industry and Information Technology on 12 October put January–September 2026 vehicle sales at 23.271 million, down 4.5% year on year. New-energy vehicle sales reached 12.472 million, up 11.1%, representing 53.6% of new vehicle sales. The total market and its powertrain mix were moving in different directions.

Figure 2. January–September 2026 vehicle-sales growth, from CAAM statistics published by MIIT. New-energy vehicles are included in total vehicle sales. Neither percentage is a measure of diode-demand growth.

For diode suppliers, the order opportunity depends on the circuit. Onboard chargers, DC/DC stages, auxiliary power supplies and communications interfaces require different devices. Changes in electrical architecture, topology and integration can change the number of diodes per vehicle. NEV growth cannot establish simultaneous growth in every automotive diode category.

Chinese suppliers already offer broad portfolios of conventional rectifiers, bridges, Zener and small-signal devices. Yangjie Technology, Good-Ark, Galaxy Microelectronics, JSCJ and Perfectway participate across several of these categories. In mature specifications, customers have multiple choices, leaving suppliers to lower die, packaging and test costs while maintaining dependable delivery. Higher sales become higher profit only when cost improvements keep pace with price reductions.

Higher switching frequency changes the comparison. FRDs require a balance among recovery behavior, losses and softness. SiC Schottky devices add trade-offs involving material cost, leakage, surge capability, packaging and converter economics. Yangjie, WeEn, CR Micro, Silan, Jilin Sino-Microelectronics and Sanan participate at different product and manufacturing stages. Techsem's high-power rectification business is closer to industrial power applications. United Nova Technology's foundry capabilities must be distinguished from revenue earned on proprietary branded devices.

Commercial progress is already visible. Sanan reports volume SiC diode deliveries to solar, storage and power customers, while Silan reports volume IGBT and FRD die deliveries to automotive-module customers. These disclosures establish adoption for the identified products. They do not establish an entire market share or qualification across every automotive grade.

Protection devices follow another demand pattern. Prisemi, Jiejie, Yingneng Microelectronics, WAYON, Shunlei, Galaxy and JSCJ participate in TVS or ESD products. Power ports prioritise surge capability and clamping; high-speed signal ports also constrain capacitance and signal loss. Verified protection has value only when the device fits the protected chip and circuit parasitics.

Yingneng's H1 2026 TVS revenue was approximately RMB 107 million, with a gross margin of 43.25%. This is a specific supplier's product-category result, not an industry average or an automotive-only figure. Its applications also include industrial equipment, telecommunications, security and consumer electronics.

WeEn, by comparison, reported a 2025 gross margin of 24.66% for silicon power diodes and negative 2.78% for SiC diodes. A July 2026 disclosure states that SiC diode gross margin became positive in January–May 2026, without an exact percentage. Material advantages can coexist with pricing, inventory and process-transition pressures.

China's established LED manufacturing base still faces pricing pressure

LEDs are a significant part of the diode industry. Sanan, HC SemiTek and Changelight participate in epitaxy and chip production, while Nationstar has packaging and application-related operations. Revenue comparisons need to distinguish chips from packaged devices and consider the processing performed by each business.

LED applications also diverge. General lighting, conventional backlighting and displays face different conditions from automotive, advanced display, ultraviolet and infrared products. Mini LED requires coordination among chips, packaging and backlight systems. Micro LED adds demanding chip fabrication, transfer, inspection and repair processes. Technical progress generates durable orders only after customer adoption and cost validation.

HC SemiTek, also known by its Chinese name Huacan, reported approximately RMB 1.281 billion of H1 2026 LED-chip revenue, up 32.10%. The business's gross margin was 8.97%, an improvement of 1.49 percentage points. Volume and cost gains were helping, but the company said industry supply still exceeded demand and prices remained materially below their year-earlier level.

Figure 3. Unaltered excerpt from page 18 of HC SemiTek's 2026 interim report. English reading guide: amounts are in RMB yuan; LED chips, substrates and other businesses are listed separately. Changes in gross margin are percentage-point changes.

Group revenue was approximately RMB 4.182 billion, up 65.15%, and included businesses such as precious-metal recycling. It cannot all be attributed to LED chips. Net profit attributable to shareholders was approximately RMB 2.05 million, while the result excluding non-recurring items remained a loss of approximately RMB 133 million.

This distinction directs attention toward chip revenue, product mix and unit cost rather than group growth alone. Automotive lighting values long-term reliability and colour consistency; display products also require efficiency, consistency and system compatibility. Manufacturing capacity becomes more valuable when those capabilities meet specific customer purchasing criteria.

China's LED industry already has a substantial manufacturing and supporting base. Further competitive gains need to be evaluated through yields, adoption and profitability in higher-value products. A blanket low-end-versus-high-end description obscures both established capabilities and significant differences among domestic companies.

Laser and detector growth produces uneven earnings outcomes

Optical communications place different demands on a light source from general lighting. Higher-speed modules require coordinated light generation, modulation, reception and electronics. A supplier's position in that upgrade can change its revenue mix rapidly.

Yuanjie reported approximately RMB 925 million of H1 2026 revenue. Data-centre products contributed approximately RMB 774 million, up 640.29%, while telecommunications products contributed approximately RMB 148 million, up 48.63%. The company reported continued volume delivery of continuous-wave, or CW, laser chips for silicon-photonics solutions and the start of volume shipments of 100G electro-absorption-modulated lasers, or EMLs. These serve different optical-module architectures: CW devices provide a continuous light source, while EMLs combine a laser with electro-absorption modulation.

Yuanjie's net profit attributable to shareholders was approximately RMB 607 million, and net profit excluding non-recurring items was approximately RMB 514 million. Its overall gross margin reached 80.42%. The company associated the increase with a larger share of data-centre products, while warning about the sustainability of that margin level. This is evidence about a particular mix and supply-demand environment, not the profitability of all laser diodes.

Suzhou Everbright Photonics, known in Chinese as Changguang Huaxin, provides a different result. Its portfolio includes high-power single emitters, bars, VCSELs and optical-communications chips. H1 2026 revenue was approximately RMB 391 million, up 82.67%. Net profit attributable to shareholders was approximately RMB 30.34 million, but the adjusted result remained a loss of approximately RMB 10.38 million. Investment-related valuation gains affected reported profit, while communications growth and inventory preparation required cash.

Figure 4. Unaltered product illustrations from page 9 of Everbright Photonics' 2026 interim report. English reading guide: the excerpt spans chips, devices and modules; it illustrates business scope, not equal production scale across every product.

The two companies participate in semiconductor lasers with different applications, ramp schedules and expense burdens. Industrial high-power lasers, communications light sources and VCSELs for consumer or automotive sensing need separate analysis. Nationstar's disclosed VCSEL volume supply and its APD development also represent different commercial stages.

Photodetectors show the same distinction. Guangte Technology covers PIN photodiodes, APDs and monitoring photodiodes. Materials disclosed in October 2026 state that its single-wavelength 100G PIN products had passed validation at some customers and secured small-volume orders. Single-wavelength 200G PIN and array products remained in sampling and evaluation. Potential next-generation demand cannot be included prematurely in existing product revenue.

Higher speed must be accompanied by performance across temperature, coupling efficiency and lifetime. Faster order growth can also require inventory and capacity spending. Reported profit, adjusted profit and operating cash flow need to be examined together.

Overseas comparisons need matched products and complete system conditions

RF diodes illustrate the limits of experience gained in conventional power devices. RF PIN devices serve switching, attenuation or limiting; varactors support tuning; Schottky devices can perform detection and mixing; and step-recovery devices address particular high-frequency functions. Frequency range, parasitics, losses and package matching shape the competition.

Yaguang Technology's H1 2026 report lists PIN, varactor, Schottky and step-recovery microwave diodes, with activities undertaken by entities including Chengdu Yaguang. Domestic products therefore exist in these categories. Whether a specific device meets a system's requirements still depends on matched specifications and validation, rather than the breadth of the company's portfolio.

In optical communications, international suppliers increasingly present coordinated chipsets. On 17 September 2026, MACOM announced a solution for 3.2T optical interconnects. Its receiver targets 448 Gb/s PAM4 per lane and combines a back-illuminated PIN photodiode with bandwidth above 100 GHz and a jointly optimised transimpedance amplifier. The offering also includes corresponding transmitter drivers.

Guangte's single-wavelength 100G and 200G product labels cannot be compared directly with a 3.2T solution's aggregate throughput. A valid assessment needs matched lane rates, modulation formats and test conditions. Announced availability is also different from completed large-scale end-customer deployment.

In September 2026, ams OSRAM presented thin-film microVCSEL arrays for AI interconnects and demonstrated a multicore-fibre connection with partners. This work still includes development and demonstration stages; it should not be counted as established volume revenue. It shows the direction of system development, while eventual customer adoption remains the commercial test.

Manufacturing models impose different constraints. An IDM has more direct control over design, process and test, while carrying plant investment and utilisation risk. A fabless supplier draws on external manufacturing but must coordinate wafer and assembly consistency. Foundries provide repeatable processes and capacity. None of these models guarantees profit independently of accepted-device cost, performance and delivery.

International suppliers face operating pressures too. For the six fiscal months ended 4 July 2026, Vishay's diode segment reported approximately US$351 million of revenue and a gross margin of 23.0%, compared with 19.9% a year earlier. The company attributed the improvement mainly to volume and average selling prices. That broad segment cannot be ranked directly against Yingneng's TVS category or Yuanjie's company-wide margin.

The next financial disclosures should make these differences more measurable. Mature rectifier businesses need cost gains that offset pricing pressure. Protection suppliers need customer validation and a profitable mix. LED companies need higher-value applications to improve margins. Laser and detector suppliers need product upgrades to keep converting into volume revenue. SiC businesses need manufacturing economics to support their system benefits.

Across these markets, new-product revenue, adjusted earnings and cash flow should support the same commercial story. Where revenue rises without better profit, pricing, inventory, R&D and depreciation remain important explanations. Where orders and earnings rise together, the next test is whether that improvement lasts through another product cycle.

Information cutoff: 26 October 2026. Financial figures retain their stated reporting periods and company or product-business scopes. Supplier examples are not a complete directory or a market-share ranking.