In one embodiment, a system is described for reducing a dark period between successive data acquisition periods associated with the detection of one or more target molecules hybridized to at least one of a plurality of probes disposed upon a biological probe array. The system comprises a switch that alternately directs an analog signal between a first circuit and a second circuit, where a period of time is required to alternate between the first and second circuits; an integrator associated with the first circuit that integrates the analog signal to generate a first integrated value; a second integrator associated with the second circuit that integrates the analog signal to generate a second integrated value; and an analog/digital converter that produces a digital value for each of the first integrated value and the second integrated values.