Abstract: Apparatus and methods configured to perform power regulation for an implantable device are presented. In an aspect, an implantable device can include a substrate that forms at least part of a body of the implantable device and a circuit disposed on or within the substrate. The circuit can include a high load power regulator configured to provide a first current level to components of the implantable device and a low load power regulator configured to provide a second current level to components of the implantable device, wherein the second current level is lower that the first current level. The circuit can also include a regulator switch configured to enable or disable current draw from the high load power regulator and the low load power regulator as a function of power state and associated power requirement of the components of the implantable device.

Abstract: Embodiments of the present invention concern the timing of sending one or more commands to control circuitry of a multi-electrode lead (MEL). In one embodiment, the one or more commands are sent to control circuitry within the MEL during a predetermined portion of a cardiac pacing cycle to avoid potential problems of prior systems that were not synchronized with the cardiac pacing cycle. In one embodiment, the one or more commands are sent when cardiac tissue is refractory from a cardiac pacing pulse, to prevent the command(s) from potentially undesirably stimulating cardiac tissue. The command sending can occur such that the one or more commands are sent between instances when sensing circuitry of the implantable cardiac stimulation device is being used to obtain one or more signals indicative of cardiac electrical activity, to prevent interference between the one or more commands with the signals indicative of cardiac electrical activity that are sensed.

Abstract: Apparatus and methods configured to perform power regulation for an implantable device are presented. In an aspect, an implantable device can include a substrate that forms at least part of a body of the implantable device and a circuit disposed on or within the substrate. The circuit can include a high load power regulator configured to provide a first current level to components of the implantable device and a low load power regulator configured to provide a second current level to components of the implantable device, wherein the second current level is lower that the first current level. The circuit can also include a regulator switch configured to enable or disable current draw from the high load power regulator and the low load power regulator as a function of power state and associated power requirement of the components of the implantable device.

Abstract: Embodiments of the present invention concern the timing of sending one or more commands to control circuitry of a multi-electrode lead (MEL). In one embodiment, the one or more commands are sent to control circuitry within the MEL during a predetermined portion of a cardiac pacing cycle to avoid potential problems of prior systems that were not synchronized with the cardiac pacing cycle. In one embodiment, the one or more commands are sent when cardiac tissue is refractory from a cardiac pacing pulse, to prevent the command(s) from potentially undesirably stimulating cardiac tissue. The command sending can occur such that the one or more commands are sent between instances when sensing circuitry of the implantable cardiac stimulation device is being used to obtain one or more signals indicative of cardiac electrical activity, to prevent interference between the one or more commands with the signals indicative of cardiac electrical activity that are sensed.

Abstract: An active feedback loop is provided in a switched-capacitor circuit to automatically cancel both junction and sub-Vth channel leakage. Low power consumption that is crucial for implantable medical devices is achieved. The circuit technique largely minimizes the effective leakage current when the switch is turned off. This circuit technique of the invention can be used in many different circuit applications.