Texas Instruments (TI) has debuted the industry’s first stand-alone active electromagnetic interference (EMI) filter integrated circuits (ICs), enabling engineers to implement smaller, lighter EMI filters, to enhance system functionality at reduced system cost — while simultaneously meeting EMI regulatory standards.

The industry’s first stand-alone active EMI filter ICs support high-density power supply designs. For more information on TI’s new power-supply filter ICs portfolio, visit TI.com/AEF.
As electrical systems become increasingly dense and interconnected, mitigating EMI is a critical system design consideration for engineers.
With innovative developments from Kilby Labs, TI’s research and development labs for new concepts and breakthrough ideas, the new portfolio of stand-alone 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.
“To meet customer needs for higher performance and lower-cost systems, TI continues to advance in power innovations to cost-effectively address EMI design challenges,” said Carsten Oppitz, GM for switching regulators at TI. “We believe that this new portfolio of stand-alone active EMI filter ICs will further help engineers solve their design challenges and maximize performance and power density in automotive, enterprise, aerospace, and industrial applications.”
Reducing size and improving reliability
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.
Mitigating common-mode emissions
Comité International Spécial des Perturbations Radioélectriques (CISPR) standards are the global benchmark for limiting EMI in electrical and electronic devices. The TPSF12C1, TPSF12C3, TPSF12C1-Q1, and TPSF12C3-Q1 help 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.
Therefore, engineers will be able to address EMI design challenges and meet CISPR 11, CISPR 32 and CISPR 25 EMI requirements.
TI’s active EMI filter ICs meet IEC 61000-4-5 surge immunity requirements, thus minimizing the need for external protection components, such as transient voltage suppression (TVS) diodes. With supporting tools, such as PSpice for TI simulation models and quick-start calculators, designers can easily select and implement the optimal components for their system.
To learn more about designing with this new family of active EMI filter ICs, read the technical article, “How a stand-alone active EMI filter IC shrinks common-mode filter size.”
Filed Under: Circuit Protection
Questions related to this article?
👉Ask and discuss on EDAboard.com and Electro-Tech-Online.com forums.
Tell Us What You Think!!
You must be logged in to post a comment.