Abstract: Generally, this disclosure provides circuitry and methods for determining the output capacitance of an output load capacitor of a power supply. The output capacitance is generally determined by beginning a calibration period and charging an output capacitor with a current source to generate an output voltage. The output voltage may be compared to a reference voltage, and a time period is determined during which the output voltage is less than the reference voltage. The capacitance value, C, of the output capacitor may be determined based on, at least in part, the determined time period. This disclosure also provides circuitry and methods to adjust certain parameters of the power supply based on the determined C value. For example, in a ramp compensation portion of the power supply, the value of a ramp capacitor and/or reset resistor may be adjusted once the value of C is determined.