High density, high performance active EMI filter for DC-DC converters

February 23, 2012 // By Paul Buckley
Vicor has introduced the Picor QuietPower QPI-21 high density active EMI filter for DC-DC converters. Supporting 48 V DC-DC converter designs up to 14 A for data communications and telecommunication applications, the QuietPower QPI-21 is an input filter that provides >99.5% efficiency while achieving a new level of filtering performance.

The QuietPower QPI-21 is packaged in a high density, 25 x 25 mm Land Grid Array (LGA) surface mount package that reduces PCB board area consumed by EMI filtering, ensuring ultra efficient board utilization. The filter’s 4.5 mm height maximizes airflow for space constrained designs, making it an ideal fit for advanced blade-architecture applications. The density advantages are complemented by new performance enhancements enabling higher frequency attenuation across various system configurations than earlier-generation QuietPower QPI-series filters.

The QuietPower QPI-21 attenuates conducted common mode (CM) and differential mode (DM) noise over the CISPR22 frequency range of 150 kHz to 30 MHz (45 dB for CM and 80 dB for DM attenuation at 250 KHz). The filter is designed for use in 48 V bus (36 – 76 V) systems, with 100 VDC/100ms surge capability, and operates over a wide temperature range of –40 to +125°C and up to an ambient temperature of 65°C without de-rating. The QPI-21 supports the PICMG 3.0 specification for filtering system boards to the EN55022 Class B limits and is also tolerant to all DC-DC converter grounding schemes.

The QuietPower QPI-21 is the newest addition to the Picor QuietPower portfolio of high density EMI input and output filters, addressing multiple voltage rail/bus needs for applications in aerospace and industrial, in addition to datacom and telecom. The QuietPower QPI-21, like all QuietPower filters, is a universal filter for use with DC-DC converters from any manufacturer.

The combination of form factor, attenuation performance, and efficiency within the QuietPower QPI-21 exceeds the capabilities of conventional passive filters making it an ideal EMI filter for demanding, high density datacom and telecomm systems with board space and/or airflow constraints.

Visit Vicor at www.vicorpower.com