There is provided a signal processing device including a signal coincidence detection portion which detects samples, in which values based on a number of times of appearance of bits coincide with each other over a plurality of samples within a pre-set period, between a first modulated signal obtained by delaying an input signal obtained by modulation and a second modulated signal obtained by subjecting the input signal to the modulation again, a signal changeover portion which switches between the first modulated signal and the second modulated signal for outputting, and a switching control portion which controls the switching between the first modulated signal and the second modulated signal by the signal changeover portion in the samples in which the values based on the number of times of the appearance coincide with each other obtained by the signal coincidence detection portion.

A system for determining one or more coefficients of a filter is presented. The system includes a modulated ramp generator including a ramp generator, a delta-sigma modulator coupled to the ramp generator and configured to generate a control signal, and a control output coupled to the delta-sigma modulator and configured to receive the control signal; and a filter coupled to the control output and configured to receive the control signal from the control output, the filter including one or more configurable coefficients, values of the configurable coefficients being selected by the control signal, an input for receiving a filterable signal, and an output for providing a filtered signal.