Circuit for switching working mode of charge pump under on-load condition without power failure and implementation method of circuit

Abstract

The invention discloses a circuit for switching the working mode of a charge pump under an on-load condition without power failure and an implementation method of the circuit. The invention mainly aims to solve the problem that an existing charge pump needs to be shut down and restarted when switching the different working modes of the charge pump. The circuit of the invention comprises an input power source control switch S_in_vx, a capacitor CX, a current source I _ PD2, a subtracter SUB 1, a subtracter SUB 2, a multiplying unit MUL 1, a multiplying unit MUL 2, an operational amplifier OP1,an operational amplifier OP 2, a passive current limiting circuit, voltage clamping circuits A1, A2 and A3, a voltage clamping and current limiting circuit and the like which are all connected with the VX pin of a charge pump chip. According to the circuit and the implementation method of the circuit provided by the invention, different connection modes of an input power source and an output loadin the circuit of the charge pump chip can be realized through switching on and switching off switches, so that the charge pump can present different working modes, and therefore, the working modes ofthe charge pump can be realized under an on-load condition without power failure. Thus, the method has high use value and popularization value.

Description

technical field [0001] The invention relates to a circuit for switching the working mode of a charge pump, in particular to a circuit for switching the working mode of the charge pump without power-down under load and its realization method. Background technique [0002] Charge pumps are switching converters that use capacitors to store energy, where switches are used to switch the capacitors between supply and discharge states, thereby raising or lowering the supply voltage. In mobile terminals or portable electronic devices, the voltage of the power supply may be lower than the operating voltage, and the charge pump can provide the voltage of the power supply to work after the system, for example, the voltage generated by the charge pump is in the range of 3.3V to 4.0V, so as to meet Electronic equipment needs to work. [0003] figure 1 The schematic diagram of the connection of the charge pump and direct transfer switch is shown. The circuit has four working modes in th...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a circuit and its implementation method for switching the working mode of the charge pump without power-off under load, which mainly solves the problem that the existing charge pump needs to be shut down and restarted when switching between different working modes

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