MCOTS-F-28-P-QT SynQor Worldwide Headquarters, MCOTS-F-28-P-QT Datasheet - Page 5

• Manufacturer Part Number: MCOTS-F-28-P-QT
• Description: Military Cots Emi Filter
• Manufacturer: SynQor Worldwide Headquarters

Product # MCOTS-F-28-P-QT
Basic Operation and Features
This module is a multi-stage differential-mode and common-mode
passive EMI filter designed to interface a power source with one or
more Mil-COTS dc-dc converters (or other loads that create EMI).
Each stage of this filter is well damped to avoid resonances and
oscillations, and only X7R multi-layer ceramic capacitors are used.
This Mil-COTS EMI filter includes a large bulk capacitor with a
series damping resistor to correct for the unstabilizing effect of a
converter’s negative input resistance. A white paper discussing
this negative input resistance and the need for corrective
damping can be found on the SynQor website (see Input System
Instability application note).
A typical application would place the Mil-COTS filter close to
the input of the dc-dc converter. The Input common-mode pin
would be connected to the chassis ground that is common with
the system input line filter or other earthed point used for EMI
measurement. The output common-mode pin would be connected
to the output ground or plane of the power converters with as
low inductance a path as possible. There are no connections to
the metal baseplate, which may also be connected to the chassis
ground if desired.
Do not connect the outputs of multiple Mil-COTS filters in parallel.
Connecting filters in this manner may result in slightly unequal
currents to flow in the positive and return paths of each filter.
These unequal currents may cause the internal common-mode
chokes to saturate and thus cause degraded common-mode
rejection performance.
Technical Specification
Phone [phone]
www.synqor.com
Figure 1: Typical Common Mode and Differential Mode Attenuation provied by
the filter as a function of frequency. both input lines are connected to chassis
ground through 50Ω resistors.
-120
-160
-200
-240
-40
-80
1.00E+04
40
0
Doc.# 005-0005228 Rev. 1
Differential
Attenuation
Common-mode
Attenuation
1.00E+05
MCOTS-F-28-P-QT
Frequency (Hz)
1.00E+06
Current:
06/15/09
1.00E+07
30A
1.00E+08
Page 5