Maxim Integrated Products, Inc.

Integrated Device Technology, Inc.

Daniel Linebarger

Gary L Wagner

Konstantin A Kouznetsov

Integrated circuit oscillators include a cascaded arrangement of first and second all-pass networks containing a resonator therein, such as a crystal-based resonator. The second all-pass network is configured to provide negative feedback to the first all-pass network at DC (i.e., very low frequencies) and is further configured to provide positive feedback with 90 degrees of phase to the first all-pass network at the resonant frequency of the resonator, which may be the third overtone frequency of a crystal resonator. The first all-pass network includes the resonator and the second all-pass network includes a resistor having resistance matched to a motional resistance of the resonator at the resonant frequency.

Third overtone crystal-based oscillators having tunable all-pass RC filters therein

The present invention is a method and system for a fully programmable modulus pre-scaler. In one embodiment, the pre-scaler is a cascade of fully programmable divide-by-&frac23; sections. A fully programmable divide-by-&frac23; section includes a state machine and a control circuit. The state machine generates a modulus control output synchronously with a clock signal in response to a modulus control input and a programming signal. The state machine has a plurality of states corresponding to a &frac23; divider. The control circuit is coupled to the state machine to generate the programming signal to the state machine in response to a programming word for a frequency divider.

Growing community of inventors

Los Gatos, CA, United States of America

Daniel Linebarger