A Digital Multi-Mode Multi-Phase IC Controller for Voltage Regulator Application

This paper presents a digital multi-mode multi-phase IC controller for the voltage regulator application. The IC controller combines load current feedforward with a load-scheduled digital PID feedback control to achieve a fast load transient response. The multi-mode control strategy is applied in the designed controller IC, allowing high efficiency operation of a voltage regulator over a wide load range. A high resolution 13-bit digital pulse width modulator (DPWM) and 4mV quantization bin analog-to-digital converter (ADC) is implemented in the IC controller to ensure tight DC regulation of the regulator. The prototype 4-phase IC controller takes 0.5 mm2 active area in a 0.18 μm CMOS process.