Patent ID: 7777585

Claim:
An oscillator circuit configured to generate a periodic signal having a free-running frequency comprising: a first circuit portion including at least one inductor coupled in parallel with at least one load capacitor, the first circuit portion having an inductance-capacitance product that has a first temperature sensitivity; and a passive circuit portion coupled in parallel with the first circuit portion, the passive circuit portion including at least one resistor in series with at least one capacitor, wherein the passive circuit portion has a second temperature sensitivity that opposes an effect of the first temperature sensitivity on the free-running frequency of the oscillator circuit, thereby reducing temperature sensitivity of the free-running frequency, wherein a temperature sensitivity of an effective capacitance (S(C EFF , T)) of the oscillator circuit is equal to - α 2 ⁢ S ⁡ ( R TC , T ) , where α<<1 and S(R TC ,T) is a temperature sensitivity of the at least one resistor.