Hero Section: The Solution

Headline:

Custom EI Core Transformers: Reliable & Cost-Effective SMPS Solutions

Sub-headline:

The industry standard for general-purpose switching power supplies. As a specialized Custom Transformer Manufacturer, we deliver EI Core Transformers that offer the perfect balance of performance, manufacturability, and cost-efficiency for consumer and industrial electronics.

Key Highlights:

Cost-Effective Design: The EI Core geometry allows for automated winding and standard bobbin usage, making it the most economical choice for mass-produced Switching Transformers.

High Inductance Capability: Capable of achieving high inductance values (e.g., 4.0mH) for specific flyback or drive applications.

Versatile Application: Proven reliability in auxiliary power supplies, white goods, and AC-DC adapters.

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Reference Case Study: Model PTX00EI33-402K

Note: The specifications below are from our production model PTX00EI33-402K. This demonstrates our manufacturing capability for Standard EI Transformers.

Parameter	Specification (Reference Only)	Customization Range
Model P/N	PTX00EI33-402K	Custom P/N assignment available
Category	High-frequency transformer	SMPS Transformer / Drive Trafo
Core Shape	EI33 (Vertical)	EI16, EI19, EI22, EI28, EI33, EI40
Dimensions	33.5 x 30.0 x 28.0 mm (Ref)	Scalable based on core size
Inductance (L)	4.0 mH ± 10% (@1kHz)	100µH - 10mH (Custom Gap)
DCR (Resistance)	< 2.5 Ω (High Turns)	Dependent on wire gauge
Pins	10 Pins (5+5)	Custom Pinout / Flying Leads
Insulation	Varnish / Tape Barrier	Reinforced Insulation available

Engineer's Insight: The PTX00EI33 features a high inductance of 4.0mH (Code 402K), suggesting a design optimized for specific high-voltage or low-frequency flyback applications. The EI33 structure provides a robust mechanical platform with 10 pins for complex multi-winding configurations.

Tailor This Transformer to Your Needs

Why choose an EI Core Transformer for your next project?

The Economic Workhorse

● Standardization: EI cores are available globally with standardized bobbins (Vertical/Horizontal). This drastically reduces tooling costs and lead times compared to custom shapes.

● Ease of Winding: The simple bobbin structure supports high-speed automated winding, ensuring consistency for high-volume orders of Custom Transformers.

Flexible Customization

● Air Gap Adjustment: We precisely grind the center leg of the EI core to adjust the Air Gap, allowing us to tune the inductance (Al value) to prevent saturation in Flyback topologies.

● Multi-Output: EI bobbins typically have ample pin counts (e.g., 10-14 pins), making them ideal for power supplies requiring multiple output voltages (e.g., +5V, +12V, -12V).

Industries We Serve

Typical applications for our EI Series Transformers.

Home Appliances (White Goods):

Auxiliary power supplies in washing machines, AC units, and refrigerators.

Industrial Control:

Bias power supplies for motor drives and relays.

Consumer Adapters:

Standard AC-DC wall chargers and desktop power supplies.

Lighting:

Ballasts and simple LED driver circuits.

Quality Assurance & Testing

Strict verification for Mass Production.

Turn Ratio & Polarity: Automated verification to ensure correct voltage output and phase.
Inductance Tolerance: 100% sorting to ensure L value (e.g., 4.0mH ±10%) meets the design spec.
Hi-Pot Testing: 3000Vac isolation testing between primary and secondary windings for safety compliance.
Impregnation: Varnish dipping to prevent core noise and improve moisture resistance.