Patent ID: 7225018

Claim:
An implantable medical device comprising: an implantable defibrillation lead including one or more defibrillation electrodes; and an implantable defibrillator coupled to the defibrillation lead, the implantable defibrillator including: a therapy circuit to deliver shock therapy via the defibrillation lead, the therapy circuit having a voltage generator circuit including: a power source, the power source having output terminals; a transformer having a lead-less package, the transformer attached to a main circuit board of the pulse generator and the transformer having a primary and a secondary coil; a switch connected in series with the primary coil between the positive and negative terminals of the power source, the switch receiving an input signal to open and close the switch; a diode connected in series with the secondary coil across the terminals of a load, the load comprising a capacitive storage element connected to leads adaptable for connection to a heart; a sense circuit monitoring the voltage at the load, the sense circuit having an output signal which is a first signal when the output voltage of the voltage generator is below a selected threshold voltage and a second signal when the output voltage of the power supply is above or equal to the selected threshold voltage; and a controller, receiving the output signal of the comparator and transmitting the input signal to the switch to open and close the switch, wherein the controller closes the switch to provide power to the load when receiving the second signal and opens the switch when receiving the first signal.