A new all-in-one bandgap reference and robust zero temperature coefficient (TC) point current reference circuit

Abstract

This manuscript presents a new bandgap reference (BGR) circuit providing dual references of voltage and current in one BGR circuit. The proposed all-in-one BGR circuit combines two proportional to absolute temperature (PTAT) current branches of conventional BGR into one NMOS transistor, avoiding the mismatch of the current branches. It also generates a new complementary proportional to absolute temperature (CTAT) current by adding a positive temperature coefficient (PTC) resistor to BGR output. Combining the two opposite TC currents together, a temperature insensitive current reference with robust zero TC point against process variation can be obtained in one BGR circuit. The BGR circuit is designed and verified in a 0.5μm CMOS technology with an active area of 0.0165mm2. With 3.3-V supply voltage, the BGR circuit provides voltage and current reference of 1.25V and 13.5uA with TCs of 11.6ppm/°C and 58.5ppm/°C over the temperature range from −40°C to 85°C, respectively.