Patent ID: 7245175

Claim:
A semiconductor switch comprising: a normally on type FET that passes a current between a drain and source thereof under zero state of a gate signal; first and second normally off type FETs, each of which does not pass a current between a drain and source thereof under zero state of a gate signal, the first and second normally off type FETs being connected to the normally on type FET therebetween in series; and control means operative to turn on and turn off the normally on type FET based on turning on or turning off the first and second normally off type FETs, the control means including; a first diode having one electrode connected to the source of the first normally off type FET; first current supply means for supplying a current to the first diode; a second diode having one electrode connected to the source of the second normally off type FET and having the other electrode connected to the other electrode of the first diode; and second current supply means for supplying a current to the second diode; wherein a junction between the other electrode of the first diode and the other electrode of the second diode is connected to a gate of the normally on type FET.