公开(公告)号：US20130314062A1

公开(公告)日：2013-11-28

申请号：US13953317

申请日：2013-07-29

Applicant: Wolfson Microelectronics plc

Inventor： Andrew Notman ,  Mark McCloy-Stevens ,  Dauglas James Wallace MacFarlane ,  Holger Haiplik

IPC: G05F1/46

CPC classification number: H02M3/1588 ,  H02M1/38 ,  H02M2001/0009 ,  H02M2001/0032 ,  Y02B70/1466

Abstract: Methods and apparatus for control of DC-DC converters, especially in valley current mode. The DC-DC converter is operable so that a low side supply switch may be turned off, before the high side supply switch is turned on. During the period when both switches are off the current loop control remains active and the change in inductor (L) current is emulated. One embodiment uses a current sensor for lossless current sensing and emulates the change in inductor current by holding the value of the output of the current sensor (ISNS) at the time that the low side switch turns off and adding an emulated ramp signal (VISLP) until the inductor current reaches zero. Embodiment employing a pulse-skip mode of operation based on a minimum conduction time are also disclosed. The invention enables a seamless transition from Continuous Conduction Mode the Discontinuous Conduction Mode and Pulse Skipping and provide converters that are efficient at low current loads.

Abstract translation: 用于控制DC-DC转换器的方法和装置，特别是在谷电流模式下。 在高侧供电开关接通之前，DC-DC转换器可操作使得可以关闭低侧供电开关。 在两个开关断开期间，电流环路控制保持有效，并且仿真电感（L）电流的变化。 一个实施例使用电流传感器进行无损耗电流检测，并通过在低侧开关断开时保持电流传感器（ISNS）的输出值并添加仿真斜坡信号（VISLP）来模拟电感器电流的变化， 直到电感电流达到零。 还公开了采用基于最小导通时间的脉冲跳过操作模式的实施例。 本发明实现了从连续导通模式不连续导通模式和脉冲跳跃的无缝转换，并提供了在低电流负载下有效的转换器。