A High Performance Parallel Negative Voltage Charge Pump

The power management circuits are a key part of chips. This paper presents a high-performance parallel negative voltage charge pump based on parallel structure. The circuit consists of two parallel charge pump which can work alternative. Based on parallel structure, the voltage conversion efficiency and reliability are increased effectively. Meanwhile, the output voltage can continuously adjust between -Vmax and 0V. The chip is simulated and fabricated with SMIC 0.18um MIXRF 1P6M process technology. The simulation results show the negative output limitation is under -4.8V under 3.3V power supply, conversion efficiency over 76%, settling time reached 150us and the voltage fluctuation less than 50mV.