Patent ID: 7245174

Claim:
A switching circuit comprising: first and second switch terminals; a switch comprising a first bipolar transistor, having a collector connected to the first switch terminal and an emitter connected to the second switch terminal, and a second bipolar transistor, having an emitter connected to the first switch terminal and a collector connected to the second switch terminal, such that the switch can be turned on by supply of a control current to the base of at least one of the first or the second bipolar transistor; and a slave switching circuit comprising: first and second slave terminals; a slave switch, the slave switch comprising a third bipolar transistor, having a collector connected to the first slave terminal and an emitter connected to the second slave terminal, and a fourth bipolar transistor, having an emitter connected to the first slave terminal and a collector connected to the second slave terminal; a first controlled current source having a programming input connected to the first slave terminal and a current output connected to the first switch terminal; and a second controlled current source having a programming input connected to the second slave terminal and a current output connected to the second switch terminal; wherein the slave switch can be turned on by supply of a slave control current to the base of at least one of the third or the fourth bipolar transistor.