DRIVING CIRCUIT FOR IGBT ELEMENT

PURPOSE:To reduce the on-resistance, while preventing the latch-up of an IGBT element by connecting a gate of an FET to a middle point of a voltage divider, and inserting its source and drain through a current path between a gate of the IGBT element and a terminal for applying a prescribed potential. CONSTITUTION:By a high gate voltage, an IGBT element Q0 is turned on with a small resistance and a collector current IC is supplied to a load. When a short circuit, etc., are generated, the current IC increases, a gate voltage connected to a middle point of a voltage divider of an FET QM rises the FET QM is turned on. As a result, a current flows to a source and a drain of the FET inserted directly to a current path provided between a gate of the element Q0 and a prescribed terminal, a gate voltage of the element Q0 drops, the element Q0 becomes an off-state and the generation of latch-up caused by an excessive current IC is prevented, and also, since usually an on-resistance is small by a high gate voltage, a power loss of the element Q0 becomes small.