CONTROL CIRCUITRY AND METHOD FOR CONTROLLING A BI-DIRECTIONAL SWITCH SYSTEM, A BI-DIRECTIONAL SWITCH, A SWITCHING MATRIX AND A MEDICAL STIMULATOR

摘要

A control circuitry (134) and a method for controlling a bi-directional switch (132) is provided. The bi-directional switch (132) having a control terminal (130) for receiving a control voltage (124) to control an on state and an off state of the bi-directional switch (132) and at least one semiconductor switch in a bi-directional main current path. The control circuitry (134) comprises an energy storage element (102), a coupling means (101) to couple the energy storage element (102) to a supply voltage to charge the energy storage element (102), and a control circuit (108) configured to receive power from the energy storage element (102) and configured to supply the control voltage having a voltage level being independent of the supply voltage when the energy storage element (102) is not coupled to the supply voltage. The coupling means (101) is configured for only coupling the energy storage element (102) to the supply voltage when the bi-directional switch (132) is in the off state.