23 00309 Low Emi Tpsf12cxx 64185fc25b3e5

Standalone Active EMI Filter ICs Support High-Density Power Supply Designs

March 20, 2023

These EMI filter ICs enable engineers to design smaller, lighter, and more affordable power supplies while optimizing system performance, efficiency, and reliability.

David Maliniak

Related To: Microwaves & RF

This article appeared in Microwaves & RF and has been published here with permission.

Check out more of our APEC 2023 coverage.

In its Booth #916 at APEC 2023, Texas Instruments (TI) is debuting the industry’s first standalone active electromagnetic interference (EMI) filter ICs, enabling engineers to implement smaller and lighter EMI filters. Such filters can enhance system functionality at reduced system cost while simultaneously meeting EMI regulatory standards.

With electrical systems growing denser and more interconnected, mitigating EMI is a critical system design consideration for engineers. TI’s new portfolio of standalone active EMI filter ICs can sense and cancel common-mode EMI by as much as 30 dB at frequencies between 100 kHz and 3 MHz in single- and three-phase AC power systems. This capability enables designers to reduce the size of chokes by 50%, compared to purely passive filter solutions, and meet stringent EMI requirements.

One of the main challenges when designing high-density switching regulators is how to implement a compact and efficient design of the EMI input filter. Through capacitive amplification, these new active EMI filter ICs enable engineers to shrink the inductance value of common-mode chokes by as much as 80%, helping to cost-effectively achieve improved mechanical reliability and increased power density.

The new family of active EMI filter ICs consists of the TPSF12C1 and TPSF12C3 for single- and three-phase commercial applications and TPSF12C1-Q1 and TPSF12C3-Q1 for automotive applications. These devices can efficiently reduce the heat generated in a power-supply EMI filter, which also extends filter capacitor lifetimes and increases system reliability.

The new active EMI filter ICs incorporate sensing, filtering, gain and injection stages. Offered in a SOT-23 14-pin package, the IC integrates compensation and protection circuitry to further reduce the implementation complexity and minimize the number of external components.

By helping to detect, process and reduce EMI in a broad range of ac/dc power supplies, on-board chargers, servers, UPS, and other similar systems where common-mode noise dominates, the devices enable designers to address EMI design challenges and meet CISPR 11, CISPR 32 and CISPR 25 EMI requirements. The ICs also meet IEC 61000-4-5 surge immunity requirements, thus minimizing the need for external protection components, such as transient-voltage-suppression (TVS) diodes.

Pre-production quantities of the automotive grade TPSF12C1-Q1 and TPSF12C3-Q1 are available now, only on TI.com, in a 4.2-mm-by-2-mm SOT-23 14-pin package. The catalog grade TPSF12C1 and TPSF12C3 will be available on TI.com in pre-production quantities by end of March 2023. Pricing starts at US$0.78 in 1,000-unit quantities. The TPSF12C1QEVM and TPSF12C3QEVM evaluation modules are available on TI.com for US$75. TI expects all devices to be available in volume production in the second quarter of 2023 and plans to release additional standalone active EMI filter ICs later in 2023.

Check out more of our APEC 2023 coverage.

About the Author

David Maliniak | MWRF Executive Editor

In his long career in the B2B electronics-industry media, David Maliniak has held editorial roles as both generalist and specialist. As Components Editor and, later, as Editor in Chief of EE Product News, David gained breadth of experience in covering the industry at large. In serving as EDA/Test and Measurement Technology Editor at Electronic Design, he developed deep insight into those complex areas of technology. Most recently, David worked in technical marketing communications at Teledyne LeCroy. David earned a B.A. in journalism at New York University.