Generating voltages above the main power supply is often a requirement in the circuit design, as it is needed for correct operation of non-volatile memory, communication or sensors. The thesis addresses the switched-capacitor voltage doubler (single stage charge pump) design for small loads, in CMOS technology.
The thesis presents the current technology's limitations, describes basic switched-capacitor voltage converters, evaluates the known topologies and presents upgrades of the chosen topology to improve reliability. Because the charge-pump output is connected to an extrenal pin, it is exposed to electrostatic discharge (ESD) damage, therefore an ESD protection circuit was designed. In conclusion, the regulation of our basic charge pump cell was added for better output voltage control, and additionaly different regulation methods are presented and compared.
The charge pump was designed in a 180 nm CMOS technology to generate sufficient photodiode array reverse bias voltage. Correct operation was verified with simulations in Cadence.
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