| 摘要 |
PROBLEM TO BE SOLVED: To reduce power consumption by cutting a current flowing through gate resistance of an upper side insulation gate bipolar transistor (IGBT) by a switch in a period when plural outputs become low. SOLUTION: PMOS transistors QP1-QPn are connected between gate terminals and collector terminals of the upper side IGBT QT1-IGBT QTn of totem-pole connected IGBTs, and the gate terminals of respective PMOS transistors QP1-QPn are controlled by a common drive circuit. At a scan drive time, by applying a fixed voltage to the gate electrodes of the PMOS transistors QP1-QPn, the currents are made a constant current, and the currents flowing through lower side IGBTs Q1-Qn are limited. In the period performing the drive that all outputs Q1-On become low, the current flowing through the lower side IGBTs Q1-Qn is cut by making the gate electrodes of the PMOSs QP1-QPn a threshold value voltage or below. Thus, the current consumed in all low period when plural channels are constituted is made nearly zero. |
