Summary: | A new precision-aware subthreshold-based MOSFET voltage reference is presented in this dissertation. The circuit is implemented TSMC-40 nm process technology. It consumes 9.6 μW at the supply voltage of 1.2 V. In this proposed work, by utilizing subthreshold-based MOSFET instead of bipolar junction transistor (BJT), relatively lower power consumption is obtained in the design whilst offering comparable precision offered by BJT counterpart. Through the proposed second-order compensation, it has achieved the temperature coefficient (T.C.) of 3.0 ppm/℃ in TT corner case and the 200-sample Monte-Carlo T.C. of 12.51 ppm/℃ over -40℃ to 90℃. This shows robust temperature insensitivity. The process sensitivity of V_ref without and with trimming is 2.85 % and 0.75 %, respectively. The power supply rejection (PSR) is 71.65 dB at 100 Hz and 52.54 dB at 10 MHz. The Figure-of-Merit (FOM) for total variation of output voltage is comparable with representative BJT circuits and better than subthreshold-based MOSFET circuits. Due to low T.C., low process sensitivity and simplicity of circuit architecture, the proposed work will be useful for sensor circuits with stringent requirement or other analog circuits that require high precision applications.
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