US 12,362,704 B2
Notch filter calibration in LC oscillators for supply noise rejection
Noam Familia, Modiin (IL); and Vadim Levin, Folsom, CA (US)
Assigned to Intel Corporation, Santa Clara, CA (US)
Filed by Intel Corporation, Santa Clara, CA (US)
Filed on Nov. 17, 2021, as Appl. No. 17/528,907.
Prior Publication US 2023/0155549 A1, May 18, 2023
Int. Cl. H03B 5/04 (2006.01); H03B 5/12 (2006.01); H03B 5/24 (2006.01); H03H 7/01 (2006.01); H03L 1/00 (2006.01)
CPC H03B 5/24 (2013.01) [H03B 5/04 (2013.01); H03B 5/1212 (2013.01); H03H 7/01 (2013.01); H03L 1/00 (2013.01); H03B 2200/009 (2013.01); H03B 2201/01 (2013.01); H03H 2007/013 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
an inductive-capacitance oscillator to receive a power supply signal from a voltage regulator and to provide an output signal having a frequency based on a voltage of the power supply signal;
one or more notch filters coupled to the voltage regulator to filter the power supply signal according to a calibration code; and
a control circuit coupled to the voltage regulator and the one or more notch filters, the control circuit is to optimize the calibration code to minimize a sensitivity of the inductive-capacitance oscillator to noise in the power supply signal, wherein to optimize the calibration code, the control circuit is to determine a first frequency of the output signal when the calibration code is an initial value and the voltage of the power supply signal is a first voltage, to determine a second frequency of the output signal when the calibration code is the initial value and the voltage of the power supply signal is a second voltage, greater than the first voltage, and to adjust the calibration code based on whether the first frequency exceeds the second frequency.