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PMP15002: Information about the Common Mode Inductor used L1

Prodigy 90 points

Replies: 3

Views: 73

Part Number: PMP15002

Hi,

I am doing research on this design and trying to locate various parts from the BOM of the PMP 15002. One part that I cannot find is the common mode inductor with the reference designator L2 and part number T953-0.45. Is it possible to get the specification sheet or recommended alternative part for this component?

Thanks!

  • Hello Aquiel,

    Thank you for your interest in the PMP15002 reference design for an off-line 5V, 3A flyback converter.

    Unfortunately, the designer of that circuit is no longer with TI and has left no documentation about L2.  It appears to be sourced from a vendor in China, but I could find no datasheet. 

    I suggest to take the information embedded in the PMP15002 schematic diagram and assume that it is a generic common mode inductor of value 800uH when measured with a 1kHz signal at 0.25Vrms.  Footprint information indicates that it is 5mm x 12mm in area.  Peak current information is not available, but given a 15-W output and "universal" input, we can conservatively estimate that for Pin = 20 W at 90Vac, PF> 0.5, Irms = ~0.444A, but peak current will be more like 1.33Apk.  So an equivalent part should not saturate when passing a 1.33A peak. 

    A suitable part should be available from any local electronic parts distributor.

    Regards,
    Ulrich  

  • In reply to Ulrich Goerke:

    Thank you for the response. Does the common mode inductor have to be exactly 800uH because I am having trouble locating one or can it be within the range of -+ 10 uH? The same for the T1 transformer.

  • In reply to Aquiel Godeau:

    Hello Aquiel,

    No, the CM inductor does not have to be exactly 800uH.  Most magnetic devices typically have tolerances of +/-10% around their nominal values. 10% is typical, although there can be tighter or looser tolerances.  +/-10uH out of 800uH is much tighter than necessary.  

    The tolerance of the transformer inductance is usually about the same, about +/-10%. 

    Regards,

    Ulrich