Low voltage CMOS bandgap references with temperature compensated reference current output

Techniques for designing low voltage bandgap references providing both reference voltage and current outputs are proposed. By modifying the bandgap load or the bandgap core, the temperature dependences of the voltage output and the current output can be compensated separately. Based on the proposed techniques, a IV bandgap reference was designed in a conventional 0.18um CMOS process. Opamp was not required in this design. The current consumption was 7.1μA. It achieved temperature coefficients of <;21ppm/°C and <;45ppm/°C for the voltage output and the current output, respectively, over different temperature, process, and sheet resistance variations.