Level shifter

Abstract

The invention discloses a level shifter which comprises an output end, a first input end, a second input end, a latch circuit, a level overturning pull-down circuit and a voltage clamping circuit. Thelatch circuit comprises a first PMOS tube, a second PMOS tube, a first NMOS tube and a second NMOS tube. The voltage clamping circuit comprises a first clamping device, a second clamping device, a third NMOS tube, a fourth NMOS tube, a fifth PMOS tube and a sixth PMOS tube. The level overturning pull-down circuit comprises a fifth NMOS transistor and a sixth NMOS transistor; the first clamping device is used for clamping the voltage of the grid electrodes of the fifth PMOS tube and the sixth PMOS tube; the second clamping device is used for clamping the voltage of the grid electrodes of the third NMOS tube and the fourth NMOS tube. Under the condition that the ground level of the high-voltage driving signal is changed, level conversion is completed at high speed and low power consumption,and the cost is low. A gate oxide layer of a transistor device in the level shifter can be protected from being broken down through the voltage clamping circuit, and the high voltage of the output end is isolated; zero static power consumption and rapid level overturning are achieved through the latch circuit and the level overturning pull-down circuit, and high driving capacity is achieved.

Description

technical field [0001] The invention relates to the technical field of level shifters, in particular to a level shifter applied to conversion of high-voltage drive signals from low-voltage logic signals to ground levels. Background technique [0002] In circuit applications, there is a need for level conversion of low-voltage logic signals to high-voltage drive signals that change from ground level. For example, in a dual NMOS (N-type metal-oxide-semiconductor) drive circuit in a traditional synchronous switching power supply topology, the NMOS gate drive for the high-voltage side involves a high-voltage drive signal that changes from a low-voltage logic signal to a ground level the process of level shifting. When using a bootstrap circuit to drive the NMOS gate on the high voltage side, if the bootstrap voltage is higher than 5V (volts), it may break down the thin gate oxide device in the traditional process. In order to solve the hazards of high bootstrap voltage, the tr...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to overcome the defects of high cost and large static power consumption in the prior art in which the low-voltage logic signal is converted to the high-voltage driving signal that changes to the ground level, and provides a high-speed, Low-power, high-voltage-resistant and low-cost level shifter for high-voltage drive signal conversion from low-voltage logic signals to ground levels

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