ZXYAUDIO EI19 Low-Frequency Audio Transformer - Single Phase Toroidal Autotransformer, Copper Wire Winding, Pin Leads for PCB Mounting, Customized Electrical Specification

1. Product Overview

The EI19 is a single-phase low-frequency audio transformer built in a toroidal, autotransformer configuration. It is wound with copper wire and terminated with pins, and is supplied for use in electronic equipment. Because the electrical specification of this model is customized, the winding data is agreed for each order rather than taken from a fixed catalogue value.

1T Series high-frequency pulse and drive transformer with dual-colour insulation and PCB mount

Close-up of the coil wrapping and the 1T top marking

2. Key Features

• Single-phase transformer for low-frequency audio use
• Toroidal coil structure for a compact, closed magnetic circuit
• Autotransformer configuration: input and output share one winding, so no separate secondary winding is required
• Copper wire winding for stable conductivity
• Pin leads for direct mounting and soldering
• Specified for use in electronic equipment
• Electrical specification customized to the customer's requirement
• Packed in cartons for transport and storage

Key highlights and customisation capabilities: custom turns ratio, inductance and power ratings, OEM / ODM

Dual-colour insulation structure: high-dielectric red coil wrapping plus yellow margin tape

3. Advantages

A toroidal winding keeps the magnetic flux inside a continuous ring instead of a stack of laminations. The magnetic circuit is short and closed, so magnetic efficiency is high, leakage inductance is low and very little stray field escapes towards neighbouring components. That matters in electronic equipment, where the transformer usually sits close to other parts on the same assembly.

Because the EI19 is an autotransformer, input and output share a single winding rather than using separate primary and secondary windings. A tapped winding of this kind needs fewer windings and a simpler coil build, which makes the part compact and economical where a shared winding is sufficient for the circuit. It is intended for low-frequency audio signals in electronic equipment.

The winding is made from copper wire, which keeps resistance low and conductivity stable, and the leads are brought out as pins so the transformer can be mounted and soldered directly onto an assembly. Since the electrical specification is customized, the winding can be built to the customer's own requirement instead of a fixed standard value, and finished units are packed in cartons.

High-permeability ferrite core and low core loss at high frequencies

4. Applications

The transformer is specified as an audio transformer for electronic equipment and operates at low frequency.

• Low-frequency audio circuits in electronic equipment
• Autotransformer signal transfer between taps of a shared winding
• Compact toroidal transformer positions in electronic assemblies
• OEM builds where a customized electrical specification is required
• Equipment that uses pin-mounted transformers for direct board assembly

Industrial and power electronics applications: MOSFET / IGBT gate drive, SMPS and DC-DC converters, inverters and EV chargers

Transformers mounted on a PCB assembly

5. Specifications

5.1 Specification

Note: the rows above are transcribed from the specification table supplied for this model.

5.2 Model Overview

Top, bottom, side and isometric views of the pin-mounted transformer

Close-up of the pin leads and moulded bobbin

6. Quality & Testing Assurance

• Quality for the EI19 is defined by the electrical specification agreed for each order, which is confirmed before production and followed during winding and assembly.
• Single-phase toroidal autotransformer construction with a copper wire winding.
• Pin leads provided as the standard lead way for direct mounting and soldering.
• Electrical specification customized per order, so each batch is built to the agreed winding data.
• Units packed in cartons for transport and storage.
• Model designation EI19 marked on the supplied specification.

Quality assurance and testing standards: 100% Hi-Pot and turns ratio / inductance tested

Units under electrical test on the bench

Model: EI19  |  Type: Low-Frequency Audio Transformer  |  Configuration: Toroidal Autotransformer, Single Phase. Electrical specification is customized per order: please send your winding data, quantity and destination port for a quotation.