Patent ID: 7388398

Claim:
An inverter irrelative to voltage, temperature, and process with an adjustable threshold, the inverter comprising: an input end for receiving an input signal; an output end for outputting an inverted signal of the input signal; a first P-type Metal Oxide Semiconductor (MOS) transistor comprising: a gate coupled to the input end; a drain coupled to the output end; and a source coupled to a bias source; a first N-type MOS transistor comprising: a gate coupled to the input end; a drain coupled to the output end; and a source coupled to a ground end; and an adjustable current source coupled to the output end for outputting current with adjustable size and adjusting the threshold of the inverter, the adjustable current source comprising: an auxiliary MOS transistor comprising a gate coupled to a controllable voltage source for outputting a first current according to a voltage outputted from the controllable voltage source; and a current mirror coupled between the auxiliary MOS transistor and the output end for outputting a second current to the output end according to the first current.