Research Of High Efficiency Charge Pump Applied To Smart Home

With the increasing development of economy and requirement of people's life quality, the intelligent life will be an inevitable trend for people's high quality life. Under the call of the 12th Five-Year Plan, the smart home market's development prospect faces new opportunities. However, smart home sensors and other subsystems have been constrained by battery life. To use new energy and to extend the battery life are the effective solutions to frequent replacement of the battery in smart home. The charge pump system has the characteristics of low power voltage requirements, high conversion efficiency, lower noise, etc, which has practical significance in applying to the new energy sources and extending battery life.Based on SMIC 55nm CMOS technology, two charge pump systems have been designed in view of two schemes above. In the new energy scenario, due to the low output voltage of the new energy source which cannot conduct the power transistor for ordinary boost circuit, generally only 0.3V to 0.6V, a charge pump boost system consisting of the ring oscillator, the non-overlapping clock circuit and the charge pump nuclear, is designed to achieve the low voltage to high voltage conversion. To extend the battery life, a fully integrated charge pump boost system is designed. The system uses the pulse skipping modulation to realize a stable output voltage. In order to improve the power conversion efficiency of the charge pump, this topic designs a low-voltage low-power voltage reference circuit and a hysteresis comparator. Cadence Spectre tools are used to complete the front-end circuit design, layout design and post-layout verification. The results are shown as follows:the low-voltage charge pump can realize 1.15-V output voltage under the power supply voltage of 0.3 V. The rise time is only 21?s. The total current is 16.8?A. The pumping efficiency can reach 95%. The fully integrated high-efficiency charge pump system can realize a 1.2-V stable output voltage under the power supply voltage of 0.7-0.9 V. The ripple is less than 0.1 V. The system can provide the load current of 1.1 mA under the power supply of 0.8 V with only 5.1 nF capacitor. The maximum efficiency of the charge pump system can reach 73%.The charge pump systems meet the requirements of the design specifications, so it can be applied in DC/DC conversion in the smart home.