ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, v. 49, No. 1, Page. 11-17
Conventionally, pulse width modulation (PWM) controllers for DC-DC switching power converters have been implemented in pure analog circuits. However, recent research showed the possibility of digital controllers with several advantages such as robustness, fast design time, and high flexibility.
Since DC-DC converted output voltage is analog in nature, an analog-to-digital interface circuit is always essential even in digital PWM controllers. A simple and efficient delta-sigma modulator is used as a conversion circuit in our silicon implementation.