Patent ID: 11196334

Abstract:
A current limiter 200 (corresponding to an example of a current detection circuit) has a comparator 210 and a variable delay unit 220. The comparator 210 switches a comparison signal OCP from a low level to a high level when the current to be monitored, which flows through an output switch, reaches a predetermined threshold value (in the present figure, when a sense voltage Vcs reaches an overcurrent detection voltage Vocp). The variable delay unit 220 measures a first time T1 from when the output switch turns on by SET=H until when the comparison signal OCP switches to the high level and delays the comparison signal OCP by a second time T2 (=K·T12) proportional to the square of the first time T1 to generate an overcurrent detection signal Sc. The variable delay unit 220 includes a first timer 223 for measuring the first time T1 and a second timer 224 for generating the overcurrent detection signal Sc by delaying the comparison signal OCP by the second time T2.