摘要 |
The present invention relates to a simple and small-sized circuit configuration (10) for significantly reducing resettling time of a peak or zero current comparator. This circuit configuration (10) provides the comparator input stage with an alternative current path at the comparator input submitted to a large voltage variation able to disturb the DC-settings. This circuit configuration (10) comprises a pair of small transistors (P3, P4) coupled to a differential pair of transistors (Nl, N2) of the comparator input stage and having a polarity different from said pair of transistors (P3, P4). The gates of the transistors P3 and P4 share a common terminal connected to said comparator input. The currents and voltages across the comparator are always maintained close to the normal DC-setting values during the voltage transition phase. This circuit configuration (10) can be used in any current comparator for detecting a peak or a zero current, in particular, in DC-DC converters based on a switched operating mode. |