Patent ID: 8570091
Filing Date: 2013-10-29
Classification: H03K

Abstract:
1. A level shifter converting an input signal to be within a range of a first voltage range into an output signal to be within a range of a second voltage range, comprising: a leakage blocking circuit, having an input terminal coupled to receive the input signal and an output terminal coupled to provide the output signal, comprising: a plurality of first-type-channel transistors that are cascaded, wherein the first-type-channel transistor at a beginning stage has a gate which is coupled to receive the input signal and a source directly connected to a gate of the first-type-channel transistor at a secondary stage, and, at each intermediate stage, each first-type-channel transistor has a source directly connected to a gate of a subsequently cascaded first-type-channel transistor, and, the first-type-channel transistor at a final stage has a source coupled to a voltage source and a drain coupled to the output terminal of the leakage blocking circuit; and a second-type-channel transistor, having a gate which is coupled to receive the input signal, a source coupled to a common voltage, and a drain coupled to the output terminal of the leakage current block circuit, wherein every one of the first-type-channel transistors except for the one at the final stage has a drain directly connected to the common voltage.