Novel MOSFET-only bandgap voltage reference

A novel bandgap voltage reference circuit is presented. This approach eliminates the need of resistors, which not only demand area but also favor noise coupling. Moreover, only forward-biased parasitic PMOS back-body diodes are used instead of bipolar transistors. As in any bandgap reference process variations can be compensated by trimming. This can be accomplished by choosing the appropriate current mirror ratios among a discrete set. Normally, this scheme does not need startup circuit unless a very short settling time is being requested for a specific application. Two versions of the circuit have been simulated over process, voltage, temperature variations and devices mismatch (PVTM) in a 0.28μ CMOS process. These proposals are valid for low to high-voltage headroom, standard and non-standard CMOS technologies.