A voltage converter system includes a switch configured to switch between first and second states responsive to a first control signal. Timer circuitry is configured to generate a timing signal representing a duration of the first state based on input and output voltages of the voltage converter system. Control logic is coupled to the switch and the timer circuitry, and configured to generate the first control signal based on a second control signal. The second control signal is based on a feedback voltage and a reference voltage. Timer control circuitry is coupled to the control logic and the timer circuitry, and configured to: detect a phase difference between the first control signal and the second control signal; and adjust the timer circuitry to change the duration based on the phase difference.