| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-speed current switching circuit wherein the startup time of its output current is made short without increasing its current consumption, and the overshoot of its output current is suppressed. SOLUTION: By subjecting MOS transistors Q3, Q4 to ON/OFF operations, a switching circuit 12 makes the current set by a current setting circuit 11 flow selectively through first and second current paths 17, 18. A current mirror circuit 13 derives from a MOS transistor Q7 the current being in a predetermined ratio to the set current flowing through the first current path 17, and includes a feedback circuit comprising MOS transistors Q6, Q10. An output- current optimizing circuit 14 so adjusts the phase margin of the feedback circuit included in the current mirror circuit 13 as to optimize the build-up of the output current outputted from the current mirror circuit 13. |
