A resistorless switched bandgap reference topology

This work presents a novel Switched-capacitor Bandgap Reference circuit using no resistors at all. The negative drift V_EB and the positive drift V_T voltages are generated by the same PNP bipolar transistor. A switched-capacitor circuit stores and processes these voltages, generating the bandgap reference voltage in only 4 clock phases. The proposed topology was simulated in CMOS 130nm process, presenting better performance than tradicional band-gap topologies. Monte Carlo simulation shows lower variability, that results from the lower variability of capacitor ratios instead of resistor ratios and from the use of just one bipolar transistor.