Monolithic power management front end with high voltage dense energy storage for wireless powering

A monolithic power management system is proposed, enabling an energy storage density improvement of more than an order of magnitude with respect to the current state of the art. This is made possible by increasing the storage voltage V_bat towards 10V. A proof of concept prototype was designed in a 90nm bulk CMOS technology with an integrated 1.8mm dipole antenna using the surrounding energy available in the 5.8GHz ISM band. In order to achieve the large voltage conversion under aim of less than 100mV to 10V, a two stage approach is found necessary as the input impedance mismatch of a single stage passive voltage multiplier with the antenna would render the solution infeasible. First, the antenna voltage is passively rectified and multiplied to an intermediate system supply voltage V_PMU of 1.2V, aftwer which this voltage is pumped up to the storage voltage level V_bat of 10V by an active DC-DC converter. This, for a minimal system startup voltage of 53mV.