Feed-Forward Pulse Width Modulation for High Line Regulation Buck or Boost Converters

A novel feed-forward pulse width modulation (FF-PWM) technique is proposed for improving line regulation of buck or boost (BOB) converters. In order to provide a regulated supply voltage for portable devices, DC-DC converters should have a good line regulation whenever the voltage of the battery is higher or lower than the system supply voltage. Because of the consideration of cost and footprint area issues, we provide a novel BOB converter with FF-PWM, which can provide a regulated supply voltage without the use of transformers or voltage inversion. According to the value of input signals, BOB converters are also useful for dynamic voltage scaling systems or the radio frequency (RF) power amplifier (PA) because it can supply a dynamic voltage suitable for minimum power dissipation. Simulation results show the good line regulation of BOB converters due to the implementation of feed-forward pulse width modulation.