Design of power management chip for piezoelectric energy harvesting

The paper proposes a complete energy harvesting solution integrated with a low-loss AC/DC rectifier and a high efficiency low dropout regulator (LDO) optimized for micro piezoelectric energy harvester. The AC/DC module converts AC into DC and then supplies power for the following LDO circuit module, through which the whole chip can obtain a stable 3.3V output voltage. A dynamic compensation mechanism is presented to improve the loop stability of LDO, which is easier to achieve high phase margin than traditional compensation strategy. The simulation results of LDO indicate that the typical dropout is 0.4mV with 1mA load current and 61mV with 150mA load current respectively, and the typical voltage line regulation error is 0.025%/V. In addition, the typical load regulation error was 0.00018%. The results demonstrate that the proposed chip meets the requirements of power supply for wireless sensor node (WSN).