Patent ID: 11929747
Assignee: REALTEK SEMICONDUCTOR CORPORATION
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A level shifter comprising:
a latch circuit coupled between a high-voltage terminal and a pair of signal output terminals, wherein a voltage at the high-voltage terminal is a high voltage, the pair of signal output terminals includes a first output terminal and a second output terminal, the first output terminal and the second output terminal are used for outputting a first output signal and a second output signal respectively, a voltage of each of the first output signal and the second output signal falls within an output voltage range, and the output voltage range is between the high voltage and a medium voltage;
a clamping circuit coupled between the pair of signal output terminals and a medium-voltage terminal, and configured to selectively couple the pair of signal output terminals with the medium-voltage terminal according to the first output signal and the second output signal so as to limit a lower limit of the output voltage range to the medium voltage, wherein a voltage at the medium-voltage terminal is the medium voltage;
a protection circuit including a first protection transistor pair and a second protection transistor pair and configured to operate according to the medium voltage, wherein the first protection transistor pair is set between the pair of signal output terminals and the second protection transistor pair; and
an input circuit includes: an input transistor pair coupled between the second protection transistor pair and a low-voltage terminal and configured to operate according to a pair of input signals, wherein the second protection transistor pair is coupled between the first protection transistor pair and the input transistor pair, a voltage at the low-voltage terminal is a low voltage, the pair of input signals includes a first input signal and a second input signal, a voltage of each of the first input signal and the second input signal falls within an input voltage range, and the input voltage range is between the medium voltage and the low voltage.