Accumulated charge pump

Abstract

The invention relates to an accumulated charge pump, and belongs to the technical field of charge pumps. The boosting aim that an MOSFET passive driving circuit fetches the voltage from a VDS is achieved. After initialization is completed, an S4 and a D1 are cut off due to reversal of biasing of the D1, and a sub-circuit is disconnected. An S1 is closed to buffer a Ui on a C1, meanwhile, an S3 is closed to feed the voltage of an output C3 back to a C2, and an S2 is disconnected in the process. Then the S2 is closed, the S1 and the S3 are simultaneously opened to enable the C2 to be connected with the C1 in series to supply power to the C3, and accumulation of the voltage of the Ui is achieved. After completion of each work cycle, the voltage of each capacitor is that U1=Ui, U2=U3-U1, U3=N*U1+U2, and the N is the switching period number. The accumulated charge pump is applied to the MOSFET passive driving circuit, a low-power boosting type charge pump and the like.

Description

technical field

[0001] The technology belongs to the field of charge pump technology. Background technique

[0002] In the capacitance matrix of the capacitance source, MOSFETs are used to realize the series-parallel conversion of capacitances. When using active MOSFET driver chips, it is necessary to add power to each driver chip, which makes the application of MOSFETs very inconvenient. The minimum voltage driven by the power MOSFET is not lower than 10V, because the uncertainty of the load current makes the drain-source voltage drop of the MOSFET inconsistent, ranging from a few tenths of volts to two or three volts, different drain-source The voltage drop of the working current is also different. To realize passive MOSFET driving, the voltage of the driving circuit must use a booster circuit to boost the drain-source voltage of the MOSFET to above 10V for the driving circuit to work. Due to the variability of the input voltage, the output cannot be achieved using the e...

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