Research And Implementation Of On-Chip Adaptive Charge Pump Voltage Regulator Circuit

The power supply is an important part of the electronic information system.To obtain a stable and continuous power supply,it is necessary to use power source technology to perform a reasonable electric energy conversion on the primary power supply.Although,compared with the inductive voltage conversion circuit,the charge pump voltage regulator circuit has the advantages of small size,easy integration,and low EMI;compared with the linear voltage regulator,the charge pump voltage regulator circuit can realize the buck-boost function,but the charge pump voltage regulator circuit still has problems such as large output voltage ripple,weak load capacity,and long power on start-up time.How to balance various parameters well so that the charge pump voltage regulator circuit maintains stable output under wide input voltage and certain load capacity after integrated floating capacitor are important topics in the research of charge pump at present,which have attracted many scholars’ attention.The research background and development status at home and abroad of charge pump circuits are reviewed in this thesis,basic structure,working principle,and main parameters of charge pump circuits are also introduced.Then the main charge pump circuit structures and characteristics are compared and analyzed,according to the needs of the thesis,the charge pump design scheme of pulseskip modulation is selected,and each circuit sub-module is designed and simulated.After the overall circuit is simulated,the disadvantages of pulse-skip modulation are analyzed.Finally,given the shortcomings of the single modulation mode,the design scheme of the adaptive charge pump voltage stabilizing circuit is proposed based on the joint pulse-skip and variable frequency modulation mode,and the corresponding circuit sub-modules are redesigned and integrated floating capacitors on-chip are used.Due to the use of the charge pump core circuit with an auxiliary drive circuit,the threshold voltage loss and reverse current during the energy transfer process are greatly reduced,and the overall charge loss is reduced.At the same time,the fast response structure is used to directly control the wake source of the error amplifier,which effectively accelerates the power-on start time of the circuit,improves the dynamic load response capability of the circuit,and reduces the output voltage ripple.The thesis is based on the CSMC 0.18μm BCD process,and the Cadence integrated circuit design and simulation software is used to design,simulate,and layout the on-chip adaptive charge pump voltage regulator circuit.The simulation results show that the circuit can work at a power supply voltage of 2.7V～5.5V and provide a stable and reliable 5V output voltage for other modules on the chip,the maximum error rate of the output voltage is within ±2%,the output voltage ripple is less than 60 m V,and the power on start-up time is less than 60μs.The comparison of the presimulation and post-simulation results shows that the circuit basically meets the design index requirements,and the process angle simulation verifies the reliability of the circuit.