SNOSCZ5B June 2015 – October 2024 FDC2112 , FDC2114 , FDC2212 , FDC2214
PRODUCTION DATA
Every inductor has a distributed parasitic capacitance, which is dependent on construction and geometry. At the Self-Resonant Frequency (SRF), the reactance of the inductor cancels the reactance of the parasitic capacitance. Above the SRF, the inductor electrically appears to be a capacitor. Because the parasitic capacitance is not well-controlled or stable, TI recommends that fSENSOR < 0.8 × fSR.
The example inductor in Figure 8-3, has a SRF at 6.38MHz; therefore do not operate the inductor above 0.8×6.38MHz, or 5.1MHz.