1. A system for reconstructing an input signal comprising: a differentiator configured to receive the input signal and generate a first signal representing the first derivative of the input signal; a level-crossing sampling block configured to receive the first signal and generate level-crossed samples; a zero-order holding block configured to receive the level-crossed samples and generate a quantized signal; and an integrator configured to receive the quantized signal and generate a second signal representing a reconstructed signal of the input signal; wherein the quantized signal is generated using non-uniform quantization.