Delay measurement, monitoring, and compensation of an oscillator control system

A method for controlling an oscillator structure configured to oscillate about a rotation axis according to a driving signal, the method comprising:

• driving the oscillator structure to oscillate about a rotation axis according to a driving signal;
• generating, by a phase error detector, a phase error signal based on a delayed event time signal and delayed reference signal, wherein the delayed event time signal indicates measured event times of the oscillator structure oscillating about the rotation axis and the delayed reference signal indicates expected event times of the oscillator structure oscillating about the rotation axis;
• inducing, by an analog signal path, an analog delay on the event time signal thereby generating the delayed event time signal, wherein the analog signal path is coupled between the oscillator structure and the phase error detector;
• generating a reference signal that indicates the expected event times;
• generating the driving signal to drive an oscillation of the oscillator structure based on the phase error signal;
• inducing a programmable delay on the reference signal thereby generating the delayed reference signal;
• injecting a test signal into the analog signal path;
• inducing, by the analog signal path, the analog delay on the test signal thereby generating the delayed test signal;
• measuring the analog delay based on the injected test signal and the delayed test signal;
• and
• generating a configuration signal configured to adjust the programmable delay according to the measured analog delay.

A Light Detection and Ranging (LIDAR) control system, comprising:

• a microelectromechanical system (MEMS) mirror configured to oscillate about a rotation axis;
• a phase error detector configured to generate a phase error signal based on a delayed event time signal and delayed reference signal, wherein the delayed event time signal indicates measured event times of the MEMS mirror oscillating about the rotation axis and the delayed reference signal indicates expected event times of the MEMS mirror oscillating about the rotation axis;
• an analog signal path coupled between the MEMS mirror and the phase error detector, the analog signal path configured to receive an event time signal indicating the measured event times and induces an analog delay on the event time signal thereby generating the delayed event time signal;
• a control circuit configured to generate a reference signal that indicates the expected event times and generate a driving signal to drive an oscillation of the MEMS mirror based on the phase error signal;
• a programmable delay circuit configured with a programmable delay, the programmable delay circuit configured to receive the reference signal and induce the programmable delay on the reference signal thereby generating the delayed reference signal;
• and
• an analog delay measurement circuit configured to inject a test signal into the analog signal path, receive a delayed test signal from the analog signal path, measure the analog delay based on the delayed test signal, and generate a configuration signal configured to adjust the programmable delay of the programmable delay circuit according to the measured analog delay.