New curvature-coefficient-canceled technique for high-precision CMOS bandgap references

A new technique of curvature-coefficient-canceled for CMOS bandgap voltage reference is presented, which takes advantage of the self-controlled theory to obtain the V_REF and the logarithmic voltage used to cancel the nonlinear term of V_BE simultaneously. This technique is implemented by two structures whose V_REF are obtained by resistive subdivision approach and mixed mode topology respectively, which are designed in standard CMOS technology with V{iTN}=0.4 V and V_TP=-0.5 V. Simulation results indicate that the reference voltages are 783 mV and 777 mV, the temperature coefficients (TC) are 2.1 ppm/°C and 3.3 ppm/°C, respectively. The power supply rejection (PSR) of both circuits are less than -30 dB below 10 kHz. These circuits dissipate about 50 uW and 60 uW at 25°C with a 1 V supply, respectively. Multiple arbitrary sub-references can be obtained due to the use of voltage regulator in the circuits.