We have used an LM3679 to step down from 3.6V (battery) to 1.8V DC for a low power (< 20mA) application.
When designed as per the data sheet (using 1.0uH inductor) the switcher radiates noise that interferes with a Near Field Magnetic Induction (NFMI) wireless communication operating at 10.6MHz.
We have found that replacing the switching inductor with a 2.2uH inductor the interference is significantly reduced. However we are unsure if this will be a solution in mass production.
The NFMI wireless communication has a centre frequency at 10.6MHz with 600 Mhz bandwidth.
Can you confirm that switching harmonics will not be produced in the 10.3Mhz to 10.9 Mhz band if we use the 2.2uH inductor?
Is it reasonable to use the larger inductor value as the datasheet recommends 1.0uH?