Patent ID: 7623916
Filing Date: 2009-11-24
Classification: A61B,A61N

Abstract:
1. An implantable cardiac stimulus device comprising: input circuitry for receiving a signal; electrodes coupled to the input circuitry to provide a cardiac signal for analysis; and a recharge circuit coupled to the input circuitry; wherein an input offset voltage occurs at the input circuitry; and wherein the implantable cardiac stimulus device is configured to: identify whether a change in the input offset voltage is likely; and if so, operate the recharge circuit to accommodate changes to the input offset voltage; wherein the input circuitry comprises coupling capacitors, wherein the recharge circuit is coupled to the coupling capacitors; the input circuitry further comprises an ECG Amplifier for amplifying signal from the electrodes; a first of the coupling capacitors is disposed in series with a first input of the ECG Amplifier and a second of the coupling capacitors is disposed in series with a second input of the ECG Amplifier, both relative to inputs from the electrodes; the recharge circuit is selectively coupled to a first node defined between the first coupling capacitor and the first ECG Amplifier input; the recharge circuit is selectively coupled to a second node defined between the second coupling capacitor and the second ECG Amplifier input; and when the recharge circuit is operated, the recharge circuit is coupled to the first and second nodes via a relatively low impedance or no impedance.