The Design of Precision Piecewise Curvature-Corrected CMOS Bandgap Reference
Zhibiao Shao · Dianzi xuebao · 2007
This paper presented a novel piecewise curvature-corrected technology,which can be accomplished in standard CMOS process technology without any extra masks for temperature compensation.Temperature coefficient is improved by ten Com- pared to the first order compensation.This novel curvature-correcting scheme can be used in almost any process technology yielding reliable temperature compensation.The additional circuitry required for this correction is compact and is easily implemented.In SMIC 0.18μm CMOS process,a precision piecewise curvature-corrected differential bandgap reference is designed.The simulation results show that differential reference is 1.9997V,total noise is 225nV,and PSRR is 98dB.Meantime,the precision piecewise cur- vature-corrected single-end bandgap reference implemented in CSMS 0.5μm process is embedded in a monolithic 100MHz PWM BUCK DC-DC converter as reference voltage.Experimental results show that reference voltage is 1.2501V,total noise is 670nV, PSRR is 66.7dB,and temperature coefficient is improved by six.Differential or single-end reference can be under 1V through changing parameters due to the current mode,which is adapted to low-voltage low-power portable devices.