A High Stability Bandgap Reference Circuit without Amplifier Structure

A new high-performance bandgap reference circuit without amplifier structure is designed to address the issues of input offset voltage in traditional bandgap reference circuits [1], which affects the accuracy of the reference voltage. By replacing the integrated operational amplifier with a Cascode current mirror structure, the circuit can be clamped and voltage conversion can be achieved. This not only greatly improves the stability of the circuit, but also effectively optimizes the layout area. Simultaneously using high-order compensation to improve performance and obtain lower temperature drift coefficients. In addition, add a startup circuit to improve the overall functionality of the circuit. Design based on SMIC 0.18 μ The simulation of the circuit using Cadence Spectra using M-process shows that within the range of -45 ℃ to 125 ℃, the fluctuation range of the output voltage is less than 0.06% when the power supply voltage fluctuates from 2.8V to 3.6V; The temperature drift of the bandgap reference circuit is 6.3 ppm/℃; The power suppression ratio at low frequencies is -67dB; The chip layout area is approximately 105 μm* 94μm.