Design of low voltage bandgap reference sources with temperature compensation but without operational amplifier

A low voltage bandgap reference circuit with temperature compensation but without operational amplifier is designed.Techniques for generating both the bandgap reference voltage source and reference current source are proposed.By modifying the bandgap load or the reference core circuit in the bandgap reference circuit,the temperature dependences of the reference voltage output and the current output can be compensated separately.The Spectre is adopted to carry out the simulation verification under the condition of 0.5 μm CMOS N well technology.The simulation result shows that while they are operating at 3.3 V and in-20 ℃~100 ℃,the temperature coefficients of bandgap reference voltage source and the current source are 35.6 ppm/℃ and 37.8 ppm/℃ PSRR is-68 dB at DC,and the power supply voltage of the reference source circuit is at the range of 2.2~4.5 V.