The Study On Piezoelectric Energy Harvesting And Management Circuit

In the environmental energy, solar, vibration, temperature gradient energy harvesting technologies, vibration energy harvesting had been a hot spot recently. The paper focuses on piezoelectric vibration energy harvesting and management circuit and proposes two new piezoelectric energy harvesting and management circuits.The first piezoelectric energy harvesting and management circuit is based on the discrete components, which includes a P-SSHI circuit, a control circuit and a DC-DC circuit. The P-SSHI circuit requires only two switches, the ultra-low power consumption diode BAT54S (VD=0.32V@IF=1mA) as the rectifier. The simulation results show that the energy collected more than5times compared to conventional AC-DC circuit; DC-DC converter operates in discontinuous current mode (DCM), which helps to reduce power consumption and improve light-load efficiency. The simulation results output voltage are3.3V with0.36%accuracy and1.8V with0.2%accuracy.The second piezoelectric energy harvesting and management circuit is based on the CSMC.5μm, which includes a signal conditioning circuit, a control circuit and a P-SSHI circuit and a DC-DC circuit. The P-SSHI circuit adopts the MOS transistors instead of the diode (VD=0.7V@IF=1mA), and does not rely complex signals. The simulation results show that the energy collected more than6times compared to conventional AC-DC circuit; DC-DC converter adopts the MOS Synchronous rectified transistors instead of the diodes. The simulation output voltage results based on the constant reference voltage source are3.3V with1.03%accuracy, energy conversion efficiency up to84.3%and1.8V with1.05%accuracy, energy conversion efficiency up to64.1%.Additional, this paper presents an improved low power reference voltage source with51.32ppm/℃temperature coefficient,0.32%/V voltage coefficient,-52dB (@100Hz) PSRR. The power consumption of the low power reference voltage source is790nW with the±6%relative process variations.