| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that an HBT has less reliability because it causes damage due to secondary breakdown caused by minute imbalance in an operation in each unit element while the HBT can acquire an on-resistance lower than that of an HEMT. <P>SOLUTION: A plurality of unit elements in which a ballast resistance is connected to a base of a unit HBT are connected in parallel to form a switching element. In this way, if positive feedback causing to increase a base current and a collector current is beginning to be generated due to temperature rise in a certain unit element, the increased base current increases voltage drop on both ends of a balast resistance, and as a result, the base current decreases and the collector current also reduces. Accordingly, the damage due to secondary breakdown in a switch circuit device formed of the HBTs can be avoided and the reliability can be remarkably increased. <P>COPYRIGHT: (C)2007,JPO&INPIT |
