When designing a system to achieve higher current ratings through parallel MOSFETs, care must be taken to understand the appropriate current balance according to the product characteristics to avoid unexpected system errors.

According to the semiconductor industry recentlyAs modern applications demand higher power capabilities and parallel designs of MOSFETs increase, verification of MOSFET characteristics and design for appropriate current balance are required for correct design.

Recent industrial and automotive applications require higher current ratings, but chips can only be designed with limited current ratings, increasing the need to use high-voltage MOSFETs or connect MOSFETs in parallel to meet the performance of modern applications.

In particular, designs using parallel connection of MOSFETs are increasing recently. In the case of a single MOSFET, there is an advantage of being able to reduce the volume of the application, but it is true that it does not satisfy high voltage or is a burden in terms of price when the level is high.

MOSFET is a key component responsible for switching and signal amplification functions in industrial, automotive applications, and power supplies.

Demand is rapidly increasing due to the popularization and diffusion of electronic devices featuring high voltage and high efficiency.

Statistically, it is recorded as the most produced semiconductor to date.all.

MOSFETs are used in most power-related applications today because of their very low power requirements and fast processing speed. However, when the total current that must be handled in a power application is too high for a single switch and a single MOSFET cannot be used, the current load is shared between MOSFETs in parallel .

In this case, it is difficult to connect MOSFETs in parallel while ensuring a robust design that includes safe operation and reliability.

Experts advise that current sharing between parallel devices is often poorly understood and, if not properly designed, can lead to unexpected system failures in the field.

In particular, paralleling becomes more difficult as switching conditions and frequencies increase, making it important to understand and ensure proper current balance between MOSFETs when connecting MOSFETs in parallel, and to understand MOSFET parameters that affect current sharing, conduction losses, switching losses, and the importance of gate threshold voltage on device temperature.

According to experts, the gate resistors should also be connected separately, and the gate pattern should be laid out as uniformly as possible. And, since the current imbalance occurs momentarily at the on and off moments of the FET, it is necessary to check the extent of the imbalance, etc.

In addition, since automotive MOSFETs are designed differently from industrial MOSFETs, each MOSFET must be used according to its appropriate purpose.

MOSFET manufacturers publish their MOSFET specifications categorized by small-signal/low-power, low-voltage, and high-voltage environments .

In addition, we provide technical support for parallel connection of MOSFETs and provide solutions to help designers apply the correct methodology when designing power converters.

A semiconductor specialist companyInfineon provides a demo board that shows the MOSFETs in parallel , providing developers with adequate help when designing power converters.