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  • golanko
    New Member
    • Nov 2008
    • 1
    #1

    switched PS

    hi,
    i designed a power supply for RFID application at 125KHz using ST L5970AD according to the application sheet, and added LM7805 at the output to stabilize the voltage and to lower the ripple and noise. i still have a problem at 10% of the boards. i think the problem is with the noise level at the output. can u advice how to reduce the noise?
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