Low voltage isolation switch, in particular for a transmission channel for ultrasound applications

摘要

A low voltage isolation switch is suitable for receiving from a connection node a high voltage signal and transmitting said high voltage signal to a load via a connection terminal. The isolation switch includes a driving block connected between first and second voltage reference terminals and including a first driving transistor coupled between the first voltage reference (Vss) and a first driving circuit node and a second driving transistor coupled between the driving circuit node and the second supply voltage reference. The switch comprises an isolation block connected to the connection terminal (pzt), the connection node, and the driving central circuit node and including a voltage limiter block, a diode block and a control transistor. The control transistor is connected across the diode block between the connection node and the connection terminal and has a control terminal connected to the driving central circuit node.

主权项

1. A low voltage isolation switch, comprising:
first and second connection terminals; first and second voltage reference terminals; a driving block electrically coupled between the first and second voltage reference terminals and including:
a first driving transistor electrically coupled between said first voltage reference terminal and a driving circuit node; anda second driving transistor electrically coupled between said driving circuit node and said second voltage reference terminal; an isolation block electrically coupled to the first and second connection terminals and to said driving circuit node, said isolation block including:
a diode block electrically coupled between the first and second connection terminals;a control transistor electrically coupled across said diode block between said first and second connection terminals and having a control terminal electrically coupled to said driving circuit node;a voltage limiter block electrically coupled between the first connection terminal and the control terminal of the control transistor; and a resistor electrically coupling the isolation block to the driving circuit node.