In today's era where the energy efficiency requirements for electronic devices are becoming increasingly stringent, precise current monitoring has become a core aspect for optimizing system performance and ensuring safe operation. Whether it's new energy storage systems, industrial frequency conversion equipment, or consumer fast-charging power supplies, real-time sensing of current directly impacts efficiency improvement, fault diagnosis, and energy distribution. Suzhou VOOHU Electronic Technology Co., Ltd., with its deep expertise in magnetic components, has launched a full range of SMT current transformers, providing a cost-effective and highly reliable current sensing solution for switching power supply (SMPS) applications.



1. Why choose a current transformer?


Basic principle of current transformer:

A current transformer is an electrical device that operates based on the principle of electromagnetic induction. It is used to convert a high current on the primary side into a low current on the secondary side for measurement and protection purposes. Its basic operating principle is similar to that of a transformer, but it is primarily used for current conversion and measurement.

Principle of electromagnetic induction: When a current passes through the primary winding, it generates an alternating magnetic flux in the iron core. These magnetic fluxes induce an electromotive force in the secondary winding, which in turn produces a proportionally reduced current. According to Faraday's law of electromagnetic induction, the magnitude of the induced electromotive force is proportional to the magnitude of the primary current and is related to the transformation ratio of the transformer (the ratio of the number of turns on the primary side to the number of turns on the secondary side).
Current transformation ratio: The transformation ratio of a current transformer is one of its key parameters, which determines the transformation ratio of current from the primary side to the secondary side. For example, if the primary side current is 1000A and the secondary side output is 5A, then the transformation ratio of the current transformer is 1000:5. The selection of the transformation ratio directly affects the measurement accuracy and scope of application of the current transformer.

Compared to technologies such as shunt resistors and Hall sensors, current transformers exhibit unique advantages in non-DC applications:

Electrical isolation: Natural isolation characteristics, easily meeting safety standards such as UL/CE/IEC

Ultra-low loss: mΩ-level primary DCR design to reduce system energy loss

Temperature stability: accuracy error <±1% across the entire temperature range, with no drift throughout the life cycle

Anti-interference capability: Immune to common mode noise through magnetic coupling principle, suitable for high noise environments

Cost advantage: Simplify circuit design and reduce total BOM cost




II. Key Selection Guide

Compared to technologies such as shunt resistors and Hall sensors, current transformers exhibit unique advantages in non-DC applications: 

 III. Voohu's Star Product Matrix


The following are some of our regular mass-produced models, which also support custom development:

IV. Typical Application Scenarios


Industry: Drive motor control, industrial automation

New energy: photovoltaic inverter, DC/DC control, base station DC/DC power supply

Automotive electronics: OBC, DC/DC control



From its establishment in 2018 to its overseas expansion in 2025, Wohu Electronics has become a reliable partner for over 1,000 enterprises, thanks to its "excellent quality, competitive pricing, attentive service, and dependable delivery".

 

If you are also looking for a "hassle-free, cost-effective, and convenient" supplier of communication electronic components, why not try Wohu? After all, the choice of over 100 listed companies can't be wrong.

 

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