From EMI Exceedance to Effortless Compliance: Why World Industrial’s Soft Bridge is the New Favorite Among Engineers

I. What is a Soft Bridge?

The working principle of a soft bridge is based on the "unidirectional conductivity" of diodes, achieving positive pulse conduction and negative pulse turn-off during the rectification process. Traditional rectifier bridge diodes generate severe oscillations during turn-off, which negatively impacts EMI performance below 500kHz. Soft bridges effectively mitigate the impact on circuit EMI by improving the diode's recovery characteristics, optimizing the softness factor (tb/ta) during the reverse recovery process, and managing the associated reverse recovery current change rate (diF/dt).

II. Four Core Advantages: Why Choose World Industrial Soft Bridges?

1.Reduced BOM Costs: Soft bridges allow for the reduction or downsizing of EMI suppression components (such as X capacitors and common-mode chokes), directly lowering the overall Bill of Materials (BOM) cost of the system.

2.Enhanced System Efficiency: By suppressing high-frequency interference and the stray inductance of the AC input line, energy losses are minimized, facilitating highly efficient power supply operation.

3.Simplified Design Complexity: There is no need for complex peripheral circuits. By simply pairing it with a π-type filter, the system can easily meet EMI certification requirements, significantly shortening the development cycle.

4.Strong Compatibility: Soft bridges can serve as a direct drop-in replacement for traditional rectifier bridges without modifying existing designs. They are suitable for various application scenarios, including power adapters and PD power supplies.

III. EMI Test Comparison of Soft Bridges

Soft bridges deliver outstanding performance in both AC-DC power supplies and PD power supplies. Taking a 12V/2A adapter and a 22W PD power supply as examples, the EMI test results for World Industrial's soft bridges demonstrate:

12V/2A (24W) Adapter Power Supply:

When using a standard rectifier bridge, the EMI values exceeded the average limit in the 250kHz to 1MHz frequency range. After switching to the soft bridge, the conducted EMI below 1MHz was significantly reduced, and the test fully complied with standard limits.

22W PD Power Supply:

When using a standard rectifier bridge, the conducted EMI exceeded the average limit within the 250kHz frequency range. After switching to the soft bridge, the EMI in this frequency range was markedly suppressed, and the test successfully passed the standard requirements.

IV. Recommended Product Models

V. Target Applications