High Integration Negative Charge Pump with Dual Operation Modes

This paper presents a high integration switched capacitor negative charge pump with dual operation modes. The charge pump integrates high frequency oscillator, level shifter, logic driver and four MOSFET switches. High working frequency optimizes the configuration of capacitors and lowers the output voltage ripple. Drive circuit with dead time control avoids shoot-through current and improves the reliability. Power switches with small conduction resistance ensure the capability of output current. The charge pump can be worked in single-supply mode or dual-supply mode and the output voltage can be set to -V _CC or -3×V _CC . This circuit has been successfully fabricated by a 0.35um BCD technology. From the results, in single-supply mode, the output voltage is -4.88V and -3.96V when output is no load and 20mA, respectively. In dual-supply mode, the output voltage is -14.83V and -12.10V when output is no load and 80mA, respectively.