Patent ID: 7019986
Filing Date: 2006-03-28
Classification: H02M

Abstract:
1. A dead time generator for forming complementary on/off control signals having a dead time to be supplied to paired switching elements, comprising: first triangular wave forming means for converting a first rectangular wave signal having a duty ratio of 50% input thereto to a first triangular wave forming signal having the same inclination in monotonous increase and monotonous decrease; first comparator means for forming a second rectangular wave signal having a duty ratio of 50% shifted in phase from the first rectangular wave signal by π/2 (or −π/2) by comparing the first triangular wave signal with a first threshold level; second triangular wave forming means for converting the second rectangular wave signal to a second triangular wave forming signal having the same inclination in monotonous increase and monotonous decrease; second comparator means for forming a third rectangular wave signal having a duty ratio greater than 50% by a value corresponding to the dead time, shifted in phase from the second rectangular wave signal by π/2 (or −π/2) by comparing the second triangular wave signal with a second threshold level; and inverter means for inverting and outputting the third rectangular wave signal, and thereby outputting an on/off control signal having the same phase as that of the first rectangular wave signal and having a dead time interval.