Capacitive DC-to-DC converter with efficient use of flying capacitors and related method

摘要

A DC-to-DC converter (120) is suitable for use in an implantable medical device (5) and includes N capacitors (160, 170) and a controller (140). N is a whole number greater than one. The controller (140) is coupled to each of the N capacitors (160,170) and to an output voltage terminal (142) and has N+1 phases. During a first phase of the N+1 phases the controller (140) couples selected ones of the N capacitors (160, 170) to the output voltage terminal (142). During successive N phases of the N+1 phases the controller (140) couples other selected ones of the N capacitors (160, 170) selectively between an input voltage terminal, a power supply voltage terminal, and the output voltage terminal (142). Voltages across each capacitor of the N capacitors (160, 170) and at the output voltage terminal (142) assume respective uniquely determined values during all of the N+1 phases.