Low-voltage low-power accurate CMOS VT extractor

Circuits extracting a MOSFET's threshold voltage belong to the general category of bias circuits. Since these circuits do not process signal inputs, their power consumption should be low, while preserving high accuracy and robustness of the output against supply voltage variations and transistor mismatch. In this brief, a low-voltage low-power self-biased analog CMOS VT extractor is proposed. By utilizing novel feedback on a simple low-voltage VT extracting block, the extractor presents less than 0.3% error for wide supply voltage range, and achieves low-power consumption and self-compensation for second-order effects and mismatch. These features are supported by simulation results.