Charge pumping circuit

Abstract

A charge pumping circuit comprises a pumping unit, first to sixth switches, a fly capacitor and an output capacitor, wherein, for a first phase, an input voltage and a first voltage respectively get access to a first end and a second end of the pumping unit to charge at least one capacitor inside the pumping unit; for a second phase, the internal capacitor of the pumping unit provides charge to the fly capacitor to generate a first output voltage through the second switch on the basis of a second voltage level through the first switch; and for a third phase, the fly capacitor provides charge to the output capacitor to generate a second output voltage through the sixth switch on the basis of a third voltage level through the third switch.

Description

technical field [0001] The invention relates to a charge pumping circuit, in particular to a charge pumping circuit with reduced capacitance components. Background technique [0002] In electronic circuits, voltages of various levels are often required for circuit use. Therefore, electronic circuits are often configured with charge pump circuits to generate voltages of various levels. [0003] Figure 1 shows a circuit diagram of a known charge pump. Please refer to FIG. 1 , the charge pump circuit 100 includes switches 101 - 108 and capacitors 109 - 112 . The charge pump circuit 100 uses two control signals PH1 (first period) and PH2 (second period) to control the on and off states of the switches 101 - 108 in turn. When the control signal PH1 is at a high level, the switches 101 , 104 , 106 and 108 are turned on, and the equivalent circuit of the charge pumping circuit 100 is shown in FIG. 2A . At this time, the input voltage VIN charges the capacitor 109 until the volt...

AI Technical Summary

Problems solved by technology

[0007] For the charge pump circuit, the built-in (build-in) capacitor will occupy a large area of ​​the integrated circuit (Integral circuit, IC), increasing the cost

The external capacitor components will increase the area of ​​the circuit board, which will also increase the cost and hinder the miniaturization of the product.

Although the known charge pump circuit 100 can generate output voltages of 2VIN and -2VIN, the output voltages Yout1 and Vout2 both require a voltage stabilizing capacitor, thus increasing the cost of the circuit

In addition, although the known charge pump circuit 300 has one capacitor less than the charge pump circuit 100, the most negative voltage generated is only -VIN

However, the charge pump circuit 300 uses 4 control signals (4 periods) to generate output voltages of 2VIN and -VIN, which will reduce the efficiency of the charge pump circuit 300 and reduce the maximum load capacity.

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