【摘要】 结合脉冲宽度调制(PWM)和脉冲频率调制(PFM)功率损耗特点,提出了一种降压型PWM/PFM混合控制DC-DC变换器芯片的电路结构,大大提高了全负载范围转换效率。重点讨论了混合控制策略和PWM/PFM切换电路的设计。Hspice模拟仿真结果验证了设计的正确性。更多还原

【Abstract】 Based on the analyses of power losses in both PWM and PFM modes,a new architecture is proposed, which can switch from PWM to PFM or vice versa depending on loads,thus providing higher energy-efficiency in full load range.The operational theory of the circuit and its structure are analyzed.The control principle of PWM/PFM switch and the circuit design are discussed in particular.Finally,the design is validated by Hspice simulation.更多还原