Embedded Ldo Charge Pump Type Dc-dc Chip Research And Design

The approaching nanometer generation of large-scale integrated (LSI) circuits requires low power-supply voltage to enable low-power operation and increased battery life. Compared with the conventional DC-DC converters which require more power and larger board space, the charge pump converters works capacitors equally well for step-up or step-down applications without the need of an inductor, providing low EMI DC/DC conversion.To solve these problems, by adopting TSMC 0.5μm standard CMOS technology, a charge pump converter which can produce a regulated, low-ripple output voltage from an unregulated input voltage is presented in this thesis. The input supply voltage ranges from 1.8V to 5.5V and it can get six output voltages ranging from 2.5V to 5.5V. It has automatic step-up/step-down operation mode. This converter is thermally protected and current limited, protecting the load and regulator during fault conditions. When the converter is in shut-down mode, the quiescent current is less than 1μA.First of all, the thesis gives the basic charge pump operation principle and equivalent circuit mode. Three control modes, namely, pulse skip mode, linear mode and LDO mode are analyzed. And then, in sub-block section, the author introduces the principle and the design detail of bandgap voltage reference, Oscillator and mode selector circuit.Based on the analysis of the charge pump principle and circuit design in the beginning chapters, whose chip simulation result done by HSPICE EDA tool verifies that the IC has achieved the expectation in function and electrical characteristics.