Hello, please notice L1, L2, L3, and L4 in the following schematic

I'm wondering, as an example value, if I wanted those to be 10 uH inductors, would ferrite beads also be acceptable as opposed to an inductor? I'm can't really find a 0805 inductor with a low DC resistance, but I can find ferrite beads that have good specs.

All the ferrite beads I found on Digikey that meet my specifications have values given in impedance at 100 MHz. Since impedance is Z = jLw, I should be able to calculate impedance as being 10*10^-6 * 2pi * 100*10^6, correct? This corresponds to about 6.3 kilo ohms of impedance at 100 MHz. Am I correct?

Hi Frank,

Please don't use an inductor (wound component) in that position! If you do, there wil be a resonance at some high frequency, that will cause a lot of trouble.

The components in the diagram is marked BLM, short for MuRata BLM series chip ferrite. These are suppressors, with high loss at high frequencies. Use BLM21A series for 0805 footprint, BLM18A series for 0603 etc.

See

www.murata.com for data. Just chose the BLM chip that supports the VDDA current (100mA??), and then choose high impedance at low (1 to 10MHz) frequency.

Other vendors, like TDK, do good chip ferrites.