A dual function circuit breaker (100, 300, 400, 500), comprising: a controller (120, 320, 420, 520) programmed to detect arc faults and ground faults; a first ADC module (122, 302, 402, 502) accessible by the controller and configured to perform sampling of an arc fault signal; a second ADC module (124, 304, 404, 504) accessible by the controller and configured to perform sampling of a ground fault signal; an arc fault sensor configured to provide the arc fault signal to the first ADC module; and a ground fault sensor configured to provide the ground fault signal to the second ADC module; the dual function circuit breaker being characterized in that: the controller is programmed to access the first ADC module and the second ADC module independently of each other to obtain data for detecting the arc faults and ground faults, respectively; and the controller is further programmed to initiate the sampling of the arc fault signal by the first ADC module upon detection of a supply line zero voltage crossing, and to initiate the sampling of the ground fault signal by the second ADC module upon detection of said supply line zero voltage crossing, such that the sampling of the ground fault signal by the second ADC module does not interfere with the sampling of the arc fault signal by the first ADC module. a controller (120, 320, 420, 520) programmed to detect arc faults and ground faults; a first ADC module (122, 302, 402, 502) accessible by the controller and configured to perform sampling of an arc fault signal; a second ADC module (124, 304, 404, 504) accessible by the controller and configured to perform sampling of a ground fault signal; an arc fault sensor configured to provide the arc fault signal to the first ADC module; and a ground fault sensor configured to provide the ground fault signal to the second ADC module; the dual function circuit breaker being characterized in that: the controller is programmed to access the first ADC module and the second ADC module independently of each other to obtain data for detecting the arc faults and ground faults, respectively; and the controller is further programmed to initiate the sampling of the arc fault signal by the first ADC module upon detection of a supply line zero voltage crossing, and to initiate the sampling of the ground fault signal by the second ADC module upon detection of said supply line zero voltage crossing, such that the sampling of the ground fault signal by the second ADC module does not interfere with the sampling of the arc fault signal by the first ADC module. the controller is programmed to access the first ADC module and the second ADC module independently of each other to obtain data for detecting the arc faults and ground faults, respectively; and the controller is further programmed to initiate the sampling of the arc fault signal by the first ADC module upon detection of a supply line zero voltage crossing, and to initiate the sampling of the ground fault signal by the second ADC module upon detection of said supply line zero voltage crossing, such that the sampling of the ground fault signal by the second ADC module does not interfere with the sampling of the arc fault signal by the first ADC module.