EE-Type Bobbin

1. Structural Features

The ferrite magnetic core of an EE-Type Bobbin is shaped like two symmetrical "E" letters combined, with the width of the central leg usually equal to that of the two side legs. This symmetrical structural design ensures a more uniform magnetic field distribution when winding the coil, which helps enhance the performance of the transformer. The pins of the EE-Type Bobbin are distributed on both sides of the bobbin, and their quantity and spacing vary according to different models and application requirements. Common sizes include EE5, EE8, EE13, EE19, etc. EE-Type Bobbins of different sizes are suitable for transformers of different power levels. For example, EE5 is used for low-power transformers and often applied in auxiliary power supplies for small electronic devices, while EE19 can be used in higher-power industrial power transformers.

2. Application Scenarios

EE-Type Bobbins are widely used in various types of transformers, including low-frequency transformers and high-frequency transformers. In the low-frequency field (e.g., power-frequency transformers), EE-Type Bobbins are often used in power transmission and distribution systems to convert high voltage into low voltage suitable for household and industrial use. In the high-frequency field (e.g., EE19 switching power supply transformers), EE-Type Bobbins can achieve efficient electrical energy conversion under high-frequency operating conditions, providing stable power for electronic devices. Additionally, EE-Type Bobbins are also applied in fields such as audio transformers and pulse transformers to meet the performance requirements of transformers in different applications.

3. Performance Advantages

The symmetrical structure of the EE-Type Bobbin results in uniform magnetic field distribution and low leakage inductance, which can improve the efficiency and power factor of the transformer. Therefore, it is also widely used in bobbins for EE05 LED driver transformer bobbin. Meanwhile, due to its simple structure, relatively mature manufacturing process, and low cost, it has high cost-effectiveness in the market. Besides, EE-Type Bobbins have high versatility—products with various sizes and pin configurations are easily available, which facilitates engineers' design and application work.

4.Contact us today to explore bulk orders or request technical specifications.

Email: sales008@mycoiltech.com

Whats app ID: +86 18788862885

Name：Alex~Mycoiltech

CIQTEK continues to expand its presence in Europe with the establishment of an SEM demo station in Spain, operated by the trusted local distributor IESMAT. Located in Madrid, the demo station features a CIQTEK High-Performance and Universal Tungsten Filament SEM Microscope SEM3200, providing Spanish users with convenient access to live demonstrations, sample testing, and hands-on operation. The facility also offers professional Spanish-language service and technical consultation, helping local customers better understand and apply CIQTEK’s advanced electron microscopy technologies.

Since the installation of the CIQTEK SEM3200, IESMAT has actively organized a series of seminars and workshops throughout 2025, typically held every one to two months. These events welcome researchers and professionals from academia and industry to explore the performance and advantages of CIQTEK scanning electron microscopes through hands-on sessions and interactive learning experiences.

IESMAT SEM Workshop in January 2025

IESMAT SEM Seminar in Feb, 2025

IESMAT Most Recent SEM Seminar in Sep, 2025

The next event, IESMAT Electron Microscopy Day II, will take place on November 6, 2025, in Madrid. Participants will enjoy:

• Live hands-on electron microscopy with the CIQTEK SEM3200

• Cutting-edge analytics using EDS and EBSD

• Insights into current trends and future directions of electron microscopy in Spain

The SEM demo station at IESMAT marks an important milestone in CIQTEK’s European development strategy. It enhances local accessibility to advanced electron microscopy technologies and provides researchers with authentic, real-world experience. Through close collaboration with partners like IESMAT, CIQTEK is deepening its engagement with the European market, promoting innovation, and building stronger connections with the scientific community.

CIQTEK remains committed to empowering global users through advanced instrumentation, localized service, and continuous collaboration for scientific progress.

This week, CIQTEK was pleased to welcome the team from our Korean distributor GSEM to the CIQTEK Electron Microscope Factory in Wuxi, China. The visit included members from sales, application, and service departments, who participated in a series of intensive and professional training sessions focused on electron microscope operation and maintenance.

The CIQTEK Electron Microscope Factory serves as the company’s dedicated manufacturing and training center for electron microscopy systems. Equipped with advanced production facilities, precision assembly lines, and demonstration laboratories, the factory integrates R&D, manufacturing, quality control, and user training to ensure high performance and reliability across CIQTEK SEM, FIB-SEM, and TEM product lines.

The training was hosted by Mr. Gao, Head of the Electron Microscopy Solutions Department at CIQTEK, together with senior engineers from the CIQTEK electron microscopy team. During the program, participants received systematic instruction on key procedures such as ion pump baking, aperture position inspection, filament centering, high-resolution imaging practice, and accessory installation and calibration.

Throughout the week, the GSEM team worked closely with CIQTEK engineers to gain both theoretical and practical understanding of CIQTEK’s electron microscopy technology. The sessions were designed to ensure that GSEM’s sales and service engineers are fully equipped with the technical expertise required to support local customers in Korea, from system installation and operation to advanced troubleshooting and maintenance.

This training not only enhanced GSEM’s technical capabilities but also strengthened the partnership between CIQTEK and GSEM. With continuous collaboration in product knowledge, application support, and customer service, CIQTEK and GSEM will jointly provide more professional, efficient, and reliable solutions to the Korean electron microscopy market.

CIQTEK remains committed to empowering global partners through professional training, technical collaboration, and continuous innovation in scientific instrumentation.

In the world of wearable technology, the Q520 Smart Ring stands out by proving that meaningful health insights don't require bulky devices. Weighing just 4.2 grams with a slim 2.1mm profile, this elegantly designed ring disappears on your finger while working quietly in the background to monitor your wellbeing. Crafted from medical-grade alloy using advanced vacuum plating technology, it combines durability with a sophisticated look that transitions seamlessly from workout sessions to formal occasions.

What makes the Q520 particularly valuable is its comprehensive approach to health tracking. The ring continuously monitors your heart rhythm, blood oxygen levels, and sleep patterns, providing gentle insights into your daily health trends. Unlike smartwatches that require frequent charging, the Q520 delivers up to six days of use on a single charge, and its 5ATM water resistance means you never need to remove it for showers or swimming. The automatic activity recognition tracks exercises like running and cycling, while the companion app presents your data in clear, understandable formats.

For those seeking a discreet health companion that fits effortlessly into their lifestyle, the Q520 offers the perfect solution. It provides the essential health monitoring most people need, without the complexity or conspicuousness of larger devices, making health awareness a natural part of your daily routine.

The T5 Smart Watch brings a new level of health awareness to your daily life through its thoughtful features and elegant design. Centered around a beautiful 1.43-inch AMOLED display that stays always visible, this watch keeps your important health information readily available without being overwhelming.

What makes the T5 special is its practical approach to health monitoring. The heart health feature lets you check your heart rhythm anytime, providing helpful insights about your cardiovascular status. The 30-second health check gives you a quick overview of your stress levels and body temperature, while the blood sugar trends feature helps you understand how your levels change throughout the day. For those keeping an eye on their metabolic health, the watch also tracks indicators like uric acid and lipids.

The T5 quietly works in the background, monitoring your heart rate, blood oxygen, sleep patterns, and blood pressure around the clock. With water-resistant construction and comfortable design, it fits seamlessly into your daily routine - whether you're working, exercising, or resting. For anyone looking to stay more connected to their wellbeing, the T5 offers gentle guidance and useful insights in a package that feels both sophisticated and approachable.

In the modern power electronics field, transformers are key devices for voltage conversion, electrical energy transmission, and distribution. Their performance directly affects the stable operation of the entire system. As a core structural component of transformers, the bobbin is like the framework of a building, playing a crucial role in the transformer's performance. Today, let's delve into the world of transformer bobbins and explore the mysteries of different types such as EF, EFD, ER, EE, POT, UU, EI, and PEE.

1. Basic Understanding of Bobbins

(1) Definition and Function of Bobbins

A bobbin, commonly known as a framework or spool in Chinese, is a key component in transformers used to support and wind coils. It not only provides physical support for the coils to ensure the accuracy of the coil's shape and position during winding but also serves as electrical isolation and insulation. This prevents short circuits between coils and between coils and the iron core, ensuring the safe and reliable operation of the transformer. Figuratively speaking, the bobbin is like the "skeleton" of the transformer, giving it its basic structural form while providing the necessary conditions for efficient electrical energy conversion.

(2).Overview of Bobbin Classification Methods

①.Classification by Magnetic Core Type: This is the most common classification method, as different magnetic core types correspond to different transformer application scenarios and performance requirements. Common types include EI, EE, EF, EPC, ER, RM, PQ, UU, etc. Each type can be further subdivided by magnetic core size, such as EE5, EE8, EE13, EE19, etc. This classification ensures that the bobbin of a high frequency electronic transformer can perfectly match a specific magnetic core, thereby maximizing the transformer's performance.

②.Classification by Shape: Bobbins can be divided into vertical and horizontal types based on shape. Vertical bobbins have pins perpendicular to the mounting plane and are typically used in compact spaces where vertical transformer installation is required, such as in power modules of small electronic devices. Horizontal bobbins have pins parallel to the mounting plane, occupying more horizontal space on the circuit board. However, they have advantages in applications with height restrictions, such as the bobbin of the PEE64 power adapter transformer in some flat-type power adapters.

③.Classification by Operating Frequency: Based on the transformer's operating frequency, bobbins can be categorized into high-frequency bobbins and low-frequency bobbins. Here, "frequency" refers to the number of periodic changes in the transformer during operation (measured in Hertz (Hz), often also in kilohertz (kHz), megahertz (MHz), or gigahertz (GHz)), not the number of uses. High-frequency bobbins are usually used in high-frequency transformers, such as the bobbin of the EE13 switching power supply transformer, with operating frequencies up to tens of kHz or even several MHz. The design and material selection of such bobbins must consider high-frequency characteristics, such as reducing high-frequency losses and improving insulation performance. Low-frequency bobbins are mainly used in low-frequency transformers, such as power frequency transformers, with typical operating frequencies of 50Hz or 60Hz. Low-frequency bobbins have relatively lower requirements for high-frequency characteristics but may have higher demands for mechanical strength and stability.

④.Classification by Pin Usage: Bobbins are divided into through-hole bobbins (DIP) and surface-mount bobbins (SMD) based on pin usage. Through-hole bobbins have long pins that can be directly inserted into the through-holes of the circuit board for soldering. This mounting method offers high mechanical strength and ease of maintenance and replacement but occupies more space on the circuit board. Surface-mount bobbins have short pins or use solder pads with Surface Mount Technology (SMT), allowing direct mounting on the surface of the circuit board. They have the advantages of small space occupation and suitability for high-density assembly, and are widely used in SMD-EFD20 home appliance transformer bobbins in modern home appliances.

3.Continuous updates...

4.Contact us today to explore bulk orders or request technical specifications.

Email: sales008@mycoiltech.com

Whats app ID: +86 18788862885

Name：Alex~Mycoiltech

1.EF Type Bobbin

(1) Structural Features: The EF type Bobbin is shaped like a combination of the letters "E" and "F", typically featuring three or more pins, which are distributed on one or both sides of the Bobbin. Its magnetic core is E-shaped, with a wider central column and narrower side columns. This structural design enables better control of magnetic field distribution during coil winding, thereby improving the coupling efficiency of the transformer. EF type Bobbins come in various size specifications, with common ones including EF10, EF12, EF16, EF20, and EF25. Different sizes are suitable for transformers of different power levels. For instance, EF10 is applicable to transformers with lower power and is often used in power modules of small electronic products; while EF25 can be used in bobbins of high-power switching power supply transformers.

(2) Application Scenarios: EF type Bobbins are widely used in fields such as switching power supplies, DC-DC converters, AC-DC inverters, LED drivers, LCD power control, laptop power supplies, digital lighting, automotive navigation systems, and security systems. In these applications, EF type Bobbins, with their excellent magnetic field control capability and high power density, can effectively realize the conversion and transmission of electrical energy, meeting the power supply requirements of different devices. Taking the EF16 LED driver transformer as an example, the EF type Bobbin can be used to drive high-power LED lamp beads. By precisely controlling the parameters of the transformer, it achieves stable regulation of the LED current, ensuring the normal operation and long operational life of LED lamps.

(3). Performance Advantages: EF type Bobbins have high magnetic permeability, which allows them to achieve a large inductance in a small volume, thereby improving the power density of the transformer. Meanwhile, their structural design helps reduce leakage inductance and improve the efficiency of the transformer. In addition, EF type Bobbins have high versatility, with a variety of sizes and pin configurations available on the market, facilitating engineers to select and apply them according to different design requirements. Taking the EF20 electronic product charger transformer as an example, the transformer, relying on the three major advantages of the Bobbin—high magnetic permeability, low leakage inductance, and strong versatility—achieves a balance of volume, efficiency, and cost in the 10-18W portable fast-charging field, making it one of the core components in fast chargers for devices such as mobile phones and tablets.

2.Continuous updates...

3.Contact us today to explore bulk orders or request technical specifications.

Email: sales008@mycoiltech.com

Whats app ID: +86 18788862885

Name：Alex~Mycoiltech

ER-Type Bobbin:Structure, Application Scenarios and Performance Advantages

1. Structural Features

The magnetic core of the ER-type Bobbin is E-shaped, but its appearance is different from that of EF-type and EFD-type bobbins. The magnetic core of the ER-type Bobbin is usually relatively flat, with the height of the middle column and side columns being relatively low. This design allows the ER-type Bobbin to occupy less space in the vertical direction, making it more suitable for application scenarios with height restrictions.

The number and layout of pins of the ER-type Bobbin vary according to different models and application requirements. The common types include through-hole type and surface-mount type (SMD), such as the ER35 transformer bobbin and SMD-ER11.5 switching power supply transformer. Its size specifications include ER8, ER10, ER12, ER16, ER20, etc. ER-type Bobbins of different sizes are suitable for transformers with different power and space requirements.

2. Application Scenarios

ER-type Bobbins are often used in fields such as ER28 DC-DC conversion transformers, switching power supplies, and high-frequency transformers. They are especially widely applied in miniaturized electronic products that have strict requirements on the volume and height of transformers.

For example, in portable power supply devices like mobile phone chargers and tablet chargers, the ER-type Bobbin, relying on its flat structural design, can achieve efficient power conversion in limited space, meeting the miniaturization and high-performance requirements of devices for power supplies.

3. Performance Advantages

The flat structural design of the ER-type Bobbin enables it to have lower winding resistance and inductive loss in high-frequency electronic transformer applications, which can effectively improve the high-frequency performance and efficiency of transformers.

At the same time, due to its compact size, it can save space in miniaturized electronic products, which is conducive to realizing the slim and lightweight design of products.

In addition, the ER-type Bobbin also has strong versatility. There are various sizes and pin configurations available on the market, facilitating engineers in design and component selection.

4.Contact us today to explore bulk orders or request technical specifications.

Email: sales008@mycoiltech.com

Whats app ID: +86 18788862885

Name：Alex~Mycoiltech

In the composition of a transformer, the bobbin (framework) is rarely mentioned as frequently as the coil or magnetic core, yet it is a key component ensuring the stable operation of transformers. It not only undertakes the important responsibility of fixing the coil but also serves as a core barrier for isolating high and low voltages and resisting high-temperature erosion. The selection of bobbin materials directly affects the safety, stability, and service life of transformers. Today, we focus on our company's exclusive material solutions for products — from selection standards to quality control details, we will comprehensively explain how our company builds product competitiveness with high-quality materials.

I. Our Star Products: Precise Material-Scenario Matching Cases

The bobbin material for each transformer model of our company is the closed-loop outcome of "scenario demand → material R&D → testing and verification → mass application". The following three star products’ material solutions can intuitively demonstrate our company's customized advantages:

1. EE16 High-Frequency Transformer: Exclusive PHENOLIC Bobbin, a Stable Choice for Industrial High-Frequency Scenarios

The EE16 high-frequency transformer focuses on industrial control power supplies and small inverters. It needs to operate continuously under high frequency (20kHz-100kHz) and high voltage (1kV-3kV). Our company exclusively equips it with a customized phenolic resin bobbin:

Material Adaptability: For high-frequency working conditions, the dielectric loss of the phenolic resin is strictly controlled below 0.008, avoiding temperature rise caused by dielectric loss heating under high frequency (the measured hot-spot temperature of the transformer is reduced by 5-8℃); the breakdown voltage of 18kV/mm can cope with occasional voltage fluctuations in industrial scenarios and eliminate the risk of electric leakage.

Practical Application Value: The EE16 transformer equipped with this exclusive phenolic bobbin can operate stably for 6 consecutive years in industrial control cabinets (the industry average is 4 years), with a failure rate as low as 0.3%. It has become a designated supporting product for over 30 industrial equipment manufacturers.

2. GU25 Pot-Type Transformer bobbin: Exclusive PA66 Bobbin, a Durable Option for Automotive Scenarios

The GU25 pot-type transformer focuses on on-board power supplies and smart home controllers. It needs to withstand continuous vibration (5-500Hz) during vehicle operation and installation impacts. Our company equips it with an exclusive nylon 66 (PA66) bobbin reinforced with 25% glass fiber:

Material Adaptability: The 25% glass fiber formula enables the bobbin to have an impact strength of 8kJ/m². After the on-board vibration test (50Hz/2g acceleration for 100 hours), the structure remains undistorted and the pins do not loosen; the heat distortion temperature of 260℃ can cope with the instantaneous high temperature of 120℃ in the on-board environment and prevent the bobbin from softening.

Practical Application Value: This GU25 transformer has passed the IATF16949 automotive electronics certification and is compatible with on-board OBC (On-Board Charger) of over 10 automobile manufacturers. In the -40℃~85℃ high-low temperature cycle test, the insulation performance retention rate is 100%, meeting the strict requirements of automotive electronics.

3. EFD20 Flyback Transformer bobbin: Exclusive PM-9630 Bobbin, an Efficiency Expert for Thin-Scenarios

The EFD20 flyback transformer focuses on laptop chargers and LED driver power supplies. It needs to achieve a thin design (thickness <12mm) while bearing a power density of 10W-60W. Our company equips it with a customized modified PM-9630 bobbin:

Material Adaptability: The modified PM-9630 has a flexural strength of 85MPa even in a 0.8mm thin-walled state, without cracking during winding; its optimized fluidity enables precise molding of the thin slot structure of the EFD20, controlling the overall thickness of the transformer at 11.5mm (the industry average for similar products is 13mm). Meanwhile, its long-term temperature resistance of 150℃ can cope with the hot-spot temperature of 140℃ of the flyback transformer.

Practical Application Value: The EFD20 transformer equipped with this bobbin is compatible with laptop chargers of over 5 consumer electronics brands. When operating at full power of 60W, its temperature rise is 6℃ lower than that of similar industry products, and it meets the UL 94 V-0 flame retardant standard, achieving both thinness and safety.

II. Our Material Advantages: Controlling from the Source to Create Value for Customers

Our company's core competitiveness in bobbin materials lies not merely in selecting high-quality materials, but in establishing a complete system of "material R&D - source traceability - full-process quality control":

Exclusive R&D Capability: We have established a material R&D laboratory and customize material formulas for different product scenarios (such as low-dielectric-loss phenolic resin for EE16 and modified PM-9630 for EFD20), breaking the industry pain point of "general materials being used for all scenarios".

Source Traceability Management: We establish traceability files for each batch of materials, recording supplier qualifications, material batch numbers, and performance parameters to ensure materials are traceable and accountable.

Full-Process Quality Control: From raw material warehousing (sampling and performance testing) → production process (real-time monitoring of molding parameters) → finished product delivery (100% appearance inspection + 10% performance sampling inspection), each link is controlled in accordance with standards higher than the industry average to ensure the stable material quality of the final products.

Choosing a transformer essentially means choosing "material reliability". Our company has always adhered to the belief that "high-quality materials create high-quality products". Through exclusive customized bobbin material solutions, we provide customers in different scenarios with transformer products that are "more stable, more durable, and more adaptable".

Before cooperation, we can provide customers with test samples. Of course, we also offer product customization services. Feel free to contact us if you have any needs.

Contact us today to explore bulk orders or request technical specifications.

Email: sales008@mycoiltech.com

Whats app ID: +86 18788862885

Name：Alex~Mycoiltech

Can the Wireless WiFi TUYA Access Control System Function Stably in Harsh Outdoor Environments?

The Wireless WiFi TUYA Access Control System is engineered to operate reliably in challenging outdoor conditions, including high temperatures, humidity, and dusty environments. Its robust design and advanced features ensure consistent performance for both residential and commercial applications. Here’s a detailed breakdown of its capabilities and protection levels:

The system is built to withstand extreme temperatures, with most models supporting an operational range of -30°C to +60°C. This makes it suitable for regions with scorching summers or freezing winters.
Humidity Tolerance:It functions seamlessly in environments with 0% to 98% humidity, thanks to its sealed internal components and corrosion-resistant materials.
Dust and Debris Protection:A tightly sealed housing prevents dust ingress, ensuring long-term durability even in construction sites or areas with high airborne particulates.

Protection Level: IP66 Rating
The system holds an IP66 certification, a globally recognized standard for environmental protection:
IP6X (Dust Protection):The highest dust resistance rating, ensuring no particles can penetrate the device.
IPX6 (Water Protection):Withstands powerful water jets from any direction, making it suitable for heavy rain or pressure washing.

Key Features for Outdoor Use
Weatherproof Construction: Zinc alloy or aluminum alloy casings, combined with epoxy encapsulation, protect against rust, UV damage, and physical impacts.
Anti-Pry and Vandal-Resistant: Reinforced screws and durable materials deter tampering, ideal for public spaces.
Multi-Environment Compatibility: Works with various outdoor setups like garages, warehouses, and hotel entrances, supporting doorbell integration and electric locks.

User-Friendly Design
Touch Keypad with Backlight: Easy-to-use even in low-light conditions.
Remote Management via TUYA App: Monitor access logs, grant temporary codes, and control the system from anywhere.
Multiple Unlocking Methods: Supports fingerprint, RFID cards, PIN codes, and app-based access for added convenience.

Ideal Application
From securing residential gates to managing commercial premises, the TUYA system adapts to diverse outdoor scenarios while maintaining high security standards. Its combination of IP66 protection and smart connectivity ensures peace of mind in harsh weather or challenging environments.

For specific model details or installation guidance, consult the product manual or contact our S4A support team.

Author: Written by Ms.Anna Zhang from S4A INDUSTRIAL CO., LIMITED