Method and apparatus for self-test of defibrillation and pacing circuits including a patient isolation switch

A method for testing an isolation switch in a defibrillator, the defibrillator having an energy storage capacitor and an output circuit with a plurality of switches for coupling the energy storage capacitor to the isolation switch, and further having an output for providing defibrillation pulses to a patient, the method comprising:

• measuring a load across the output of the defibrillator;
• if the measurement of the load is higher than an expected range for a patient, then conducting an open circuit test for testing the isolation switch;
• and
• if the measurement of the load is lower than an expected range for a patient, then conducting a short circuit test for testing the isolation test.

A method for testing an isolation switch in a defibrillator, the defibrillator having an energy storage capacitor and an output circuit with a plurality of switches for coupling the energy storage capacitor to the isolation switch, the defibrillator also having an output for applying defibrillation pulses to a patient, the method comprising:

• providing control signals for making one or more of the switches of the output circuit conducting while the control signal for the isolation switch is not set to the conducting state;
• measuring a selected energy parameter that is indicative of the voltage across the output of the defibrillator;
• and
• if the energy parameter changes by more than a predetermined threshold amount, providing an error indication.

A method for testing an isolation switch in a defibrillator, the defibrillator having an energy storage capacitor and an output circuit with a plurality of switches for coupling the energy storage capacitor to the isolation switch, the defibrillator also having an output for applying defibrillation pulses to a patient, the method comprising:

• providing control signals for making one or more of the switches of the output circuit conducting while the control signal for the isolation switch is set to the conducting state;
• measuring an energy parameter that is indicative of the voltage across the output of the defibrillator;
• and
• if the energy parameter does not change by more than a predetermined threshold amount, providing an error indication.