Level shifting circuit for high voltage applications

摘要

A level shifting circuit includes a current mirror that generates a first bias current and a second bias current (proportional to the first bias current with a first ratio). A first level shifter is coupled between a first input node (receiving a first input signal) and a first output node coupled to an input of the current mirror. The first level shifter applies a first voltage variation to the first input signal in response to the first bias current. A second level is coupled between a second input node (receiving a second input signal) and a second output node coupled to an output of the current mirror. The second level shifter applies a second voltage variation (associated with the first voltage variation) to the second input signal in response to the second bias current.

主权项

1. A circuit comprising:
a current mirror configured to generate a first bias current and a second bias current, said second bias current proportional to the first bias current with a first ratio; a first level shifter having a first input node configured to receive a reference input signal and having a first output node, said first level shifter coupled to the current mirror at said first output node and configured to apply a first voltage variation to the reference input signal in response to the first bias current so as to output a first output signal at said first output node; a second level shifter having a second input node configured to receive a sense input signal and having a second output node, said second level shifter coupled to the current mirror at said second output node and configured to apply a second voltage variation in association with the first voltage variation to the sense input signal in response to the second bias current so as to output a second output signal at said second output node; an output circuit coupled to receive the first and second output signals and generate an output in response thereto; and a first overvoltage protector coupled between the second level shifter and an input of the output circuit and configured to provide overvoltage protection for the output circuit.