Charge pump and working method thereof

Abstract

The invention discloses a charge pump and a working method thereof. The charge pump comprises a reference voltage generation circuit, a voltage comparator, a clock generator, a charge transferring capacitor, a voltage-stabilizing capacitor, a first switch, a second switch, a third switch and a fourth switch; through charging the charge transferring capacitor and transferring charges on the charged charge transferring capacitor to the output end of the charge pump, an electrical level higher than an input voltage is output, and when the charge transferring capacitor is charged every time, the charge transferring capacitor is not charged fully, but is only charged to a set voltage, and then the charging is stopped. According to the invention, the conversion rate of the charge pump can be increased, and the voltage ripples output by a circuit of the charge pump are reduced.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a charge pump and a working method. Background technique [0002] A charge pump is a circuit that outputs different voltages based on a single supply voltage, typically involving twice the input voltage. Charge pumps are often used in memory circuits, especially flash memory or phase change memory that require multiple voltages to read and write properly. [0003] Such as figure 1 as shown, figure 1 It is an existing charge pump circuit for generating high voltage Vout, the output voltage Vout can be controlled by setting the reference voltage Vref. The charge pump circuit is composed of a clock generator 10, a variable resistor Rin, a charge transfer circuit 12, voltage dividing resistors R1 and R2, a voltage amplifier 13 and a reference voltage generating circuit 14, wherein Vin is the input voltage of the charge pump circuit, CLK1 and CLK2 is a two-phase non-overlapping clock gener...

AI Technical Summary

Problems solved by technology

However, due to the internal resistance of the switch tube M1, the switch tubes 54, 55, 56 and the charge pump circuit, the output voltage Vout will decrease with the increase of the load current.

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