studljmd

482 Jingba Rd, Yueqing Economic, ZJ 325600, CN

English

Empowering Industries,
Delivering Reliable Power. Committed to Excellence.

LJ-MD is a trusted manufacturer of high-performance diodes, thyristors, serving industries from renewable energy to heavy-duty industrial control. With advanced production lines, strict quality inspections, and global supply capacity, we ensure every product delivers stable performance and long-term reliability.

TÜV Rheinland & ISO certified manufacturing

Proven solutions for high-voltage and high-current demands

Worldwide logistics and technical support

Rectifier Diodes

Rectifier diodes convert AC to DC and are essential in almost every electrical system. LJ-MD offers a complete range of low and high current designs,delivering high surge capability, stable performance, and long-term reliability for industrial, renewable energy, and power transmission applications.

High surge current capability
Stud cathode and stud anode version
Wide current range

Phase Control Thyristors

Phase control thyristors regulate AC power by gating in sync with the sine wave. LJ-MD provides capsule-type and stud-type designs with high current ratings and excellent dynamic characteristics, serving DC motor drives, marine and rail propulsion, wind power converters, and electrochemical power systems..

High current rating
Excellent dynamic characteristics
Metric Device version available

Triac Thyristors

Triac thyristors control power in both halves of an AC cycle, making them ideal for AC switching applications. LJ-MD offers robust designs with high thermal stability and long service life, widely used in lighting control, motor speed regulation, heating equipment, and industrial automation systems.

High current rating
Excellent dynamic characteristics
Metric Device version available

Fast Thyristors

Fast thyristors feature low turn-off times for high-frequency switching applications. LJ-MD supplies stud-type and capsule-type options with high surge capability and reliable operation, suited for induction heating, welding equipment, UPS systems, and pulse power applications.

High current rating
Excellent dynamic characteristics
Metric Device version available

Avalanche Diodes

Avalanche diodes protect electrical systems from voltage spikes by allowing controlled breakdown at a precise voltage. LJ-MD designs high-reliability avalanche diodes with excellent surge handling, ideal for over-voltage protection in power grids, renewable energy systems, rail traction, and industrial control equipment.

High current rating
Excellent dynamic characteristics
Metric Device version available

Press-fit Diode serices

Press-fit diodes enable solderless, high-reliability connections for power electronics. LJ-MD offers press-fit designs with low thermal resistance and high surge capability, making them ideal for automotive powertrains, renewable energy inverters, railway converters, and industrial motor drives.

Diffusion structure
Low pressure drop
High inrush current capability

why choose us

A Trusted and Collaborative Partner

sustainability Governance business strategy

Our commitment is to design and manufacture power semiconductor devices that support global progress toward cleaner and more efficient energy use. We integrate advanced production processes with strict environmental controls to minimize impact and deliver reliable products for renewable energy, industrial automation, and transportation sectors.

We operate with transparency, responsibility, and accountability in every stage of our business. From raw material sourcing to final product delivery, we maintain full traceability and compliance with international quality and safety standards such as TÜV Rheinland, ISO, and CE.

Our strategy focuses on innovation, customization, and global service. We invest in R&D to deliver diodes, thyristors, and modules tailored to client needs, while maintaining rapid response times and worldwide technical support.

Promote responsible and sustainable manufacturing practices

Ensure transparent processes and consistent quality in every stage

Deliver innovative, high-performance semiconductor solutions globally

Our commitment

Harsh-Environment Proven

Our semiconductors have been field-tested in offshore wind farms, high-speed rail, and heavy industrial plants — operating flawlessly in extreme heat, cold, and high-surge conditions.

Agile Custom Engineering

We turn unique technical requirements into tailored solutions fast — from special voltage ratings to unique housings and thermal designs — without compromising quality or reliability.

Lifecycle Technical Partnership

Beyond supplying components, we provide design consultation, system optimization, and maintenance guidance, ensuring maximum uptime and performance over the product’s life.

Fast & Reliable Delivery

With optimized production planning and a dedicated logistics team, we ensure on-time delivery for urgent orders, minimizing project delays and reducing downtime risk.

working process

Efficient Work Process

From material selection to final delivery, every step of our workflow is designed to ensure quality, reliability, and efficiency. With proven processes and flexible solutions, we meet the diverse needs of our customers worldwide.

Premium Material Selection

We work with over 1,000 qualified suppliers, selecting raw materials with strict standards. Every batch is checked for stability and consistency, ensuring a solid foundation for producing reliable, high-performance power semiconductor products that meet demanding applications.

Automated Mass Production

Our advanced automated production lines manage each step with precision, minimizing human error and maximizing efficiency. This process ensures consistent quality, high yield, and compliance with industry standards for every unit we manufacture and deliver to our clients.

Strict Individual Testing

Before shipment, each product is tested individually for electrical parameters, mechanical integrity, and appearance. We maintain rigorous standards to guarantee that every item meets or exceeds the required specifications, ensuring dependable performance in the field.

Packaging And Distribution

Each unit is packed in pearl-cotton inner boxes for full protection, then placed into triple-wall corrugated cartons. This method prevents damage, preserves product integrity, and ensures safe arrival for our customers, even after long-distance global transportation.

Your Power Semiconductor Partner

At LJ-MD, we specialize in high-performance diodes and thyristors that drive renewable energy, industrial automation, and global infrastructure projects. With decades of expertise and advanced manufacturing, we partner with clients worldwide to deliver reliable solutions, enhance efficiency, and build a greener future.

let’s work together

Application Area

Innovating for a Better Future

LJ-MD’s have been widely used in wind power generation, information technology, welding equipment, heating equipment, industrial control, solar energy, electric power, rail transit,electric welding machines, industrial equipment and other fields.

verything You Need to Know

Got Questions? We’ve Got Answers!

From technical specifications to installation tips, our team provides clear, reliable answers to help you choose, use, and maintain our products with confidence.

View all questions

What is the typical service life of LJ-MD rectifier diodes?

Under proper operating conditions and with adequate heat dissipation, LJ-MD rectifier diodes deliver long-term stable performance with minimal performance degradation over time.

Can LJ-MD thyristors operate in high-surge industrial environments?

Yes. Our thyristors are designed with high surge current capability and robust thermal stability, making them ideal for heavy-duty industrial applications.

How to select the right heat sink for my application?

Select a heat sink with thermal resistance lower than the specified maximum in the product datasheet, considering ambient temperature and airflow conditions. We provide matching heat sink models for each device.

What testing and certifications do LJ-MD products have?

All products undergo 100% electrical testing, surge capability verification, and thermal cycling tests. Certifications include TÜV Rheinland, ISO, CE, and CQC.

Can products be customized for special voltage or housing requirements?

Yes. We offer customization for voltage ratings, housing types, and thermal designs to meet specific customer applications. Lead time depends on design complexity.

our latest news

News & Industry Views

Stay informed with the latest news, product updates, and expert insights from LJ-MD and the global power semiconductor industry.

Feb 25