Charge pump circuit

Abstract

Through different voltage controller, the charge pump circuit selects required output voltage. Different switching capacitors are utilized to reach voltage needed for programmable LCD driving circuit. In the invention, different output voltages are outputted from single output node through few capacitors. Being applicable to IC chip in high voltage, the charge pump realizes low power waste and high efficiency. The structure of the circuit can be extended in order to obtain voltage needed based on requirement. Features are: modular construction, programmable value of output voltage reached through logic controlled clock time sequence, high voltage generated from few stages of level carry circuit and few capacitors.

Description

technical field [0001] The most common application of charge pump circuits is in the design of erasable programmable read-only memory circuits. So far, charge pump and voltage multiplication technology have been successfully applied in the design of low-voltage and low-power analog integrated circuits in LCD / TFT / OLED design. This invention is related to LCD circuits and in particular to LCD driver designs that provide multilayer voltage converters in a high voltage BICMOS process through programmable digital logic. Background technique [0002] As technology approaches to nanometers, analog circuit design must face the challenge of lowering voltage. Many LCD designs have to use high voltages internally to meet the LCD material requirements. Therefore, on-chip charge pumps and voltage multipliers become an integral part of low-voltage analog and digital circuit designs. Such as Figure 1 It is the driving circuit of TFT (Thin Film Transistor). In order to enable the TFT p...

AI Technical Summary

Problems solved by technology

But unfortunately, as the input voltage decreases, Vφ decreases and Vd will limit the output voltage

Therefore, Dickson voltage pumps are not suitable for low pressure operation

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