Patent ID: 8618965
Filing Date: 2013-12-31
Classification: G04F

Abstract:
1. A method of calibrating at least one of a capacitive load and a charging current controlling a charge-to-digital timer, the method comprising: initializing the capacitive load and the charging current; applying first start and stop signals to the charge-to-digital timer to measure a first calibration phase during a first calibration period, said first start and stop signals separated in time by a first number of oscillator cycles; applying second start and stop signals to the charge-to-digital timer to measure a second calibration phase during a second calibration period, said second start and stop signals separated in time by a second number of oscillator cycles having a known relationship to the first number of oscillator cycles; and adjusting at least one of the capacitive load and the charging current based on the first and second calibration phases.