Design of Start-up Enabled Bandgap Voltage Reference

The voltage reference circuits are an important part of analog and mixed-signal VLSI systems. Voltage reference circuits generate constant voltage independent of temperature and supply-voltage variations. In the conventional Bandgap References (BGR) output voltage is the sum of the forward voltage drop across a diode and thermal voltage multiplied by constant. This paper proposes BGR circuit design in 180 nm technology that operates on a 3.3 V power supply and generates 1.20 V for the temperature range -$40^{\circ}\mathrm{C}$ to $140^{\circ}\mathrm{C}$ with a temperature coefficient of 12.71 ppm/oC. The layout of the proposed work is developed, and the simulation results postlayout are matched with pre-layout. The proposed Bandgap Reference (BGR) design uses only MOSFETs and BJTs. The design is analyzed theoretically and practically. The output reference voltage is observed in pre-layout and post-layout simulations using sky130 PDK The proposed design consumes 72.6 $\mu \mathrm{W}$ of power.