This paper presents a signal processing method that uses digital pulse as an intermediate signal for delta-sigma analog-to-digital conversion. Unlike conventional analog signal processing that directly uses voltage variables in amplifier-based or transconductor-based filters, the method proposed in this work converts voltage variables into digital pulse and allows the charge-pump to be implemented for loop filters, thus removes the analog building blocks mentioned above. This method circumventing conventional analog building blocks may lead to lower power consumption and favor CMOS technologies scaling. As an example, a fourth-order delta-sigma modulator based on the proposed method is presented. Behavioral simulation results show that the performance of the proposed modulator is comparable to that of the original modulator.