US 12,316,217 B1
Frequency band avoidance in an on-demand switched-power converter circuit
Bryan W. McCoy, Phoenix, AZ (US); Siddharth Maru, Austin, TX (US); and Alban Shemsedini, El Mirage, AZ (US)
Assigned to CIRRUS LOGIC, INC., Austin, TX (US)
Filed by CIRRUS LOGIC INTERNATIONAL SEMICONDUCTOR LTD., Edinburgh (GB)
Filed on May 29, 2023, as Appl. No. 18/325,036.
Claims priority of provisional application 63/398,944, filed on Aug. 18, 2022.
Int. Cl. H02M 1/44 (2007.01); H02M 3/158 (2006.01)
CPC H02M 1/44 (2013.01) [H02M 3/158 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method of reducing electromagnetic interference (EMI) by a switched-mode power supply, the method comprising:
responsive to a change in demand or input voltage of the switched-mode power supply, adjusting an operating frequency of the switched-mode power supply;
determining a disallowed cycle time period range corresponding to a band of frequencies for which the switched-mode power supply should be prevented from operating in order to avoid generating the electromagnetic interference in the band of frequencies;
detecting that a switching event of the switched-mode power supply for the adjusted operating frequency would cause a switching cycle period to be within the disallowed time period range;
responsive to detecting that the switching event of the switched-mode power supply would cause the switching cycle period to be within the disallowed cycle time period range, preventing switching of the switched-mode power supply; and
responsive to detecting that the switching event of the switched-mode power supply would not cause the switching cycle period to be within the disallowed cycle time period, permitting switching of the switched-mode power supply.