Band-gap reference source of ultra-low power supply voltage

The invention belongs to the technical field of integrated circuit design, in particular to a band-gap reference source of an ultra-low power supply voltage. The band-gap reference source comprises a subthreshold tube M1, a subthreshold tube M2, a low-voltage operational amplifier, a plurality of divider resistors, current mirrors M3, M4 and M5 and an output resistor R6. In the invention, reference voltage is supplied under the ultra-low power supply voltage (less than 0.6V) by utilizing the temperature characteristic of an MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) working in a subthreshold area and the characteristic of low voltage at the two ends of the MOSFET and matching with the low-voltage operational amplifier. The output voltage of the reference is relative to the resistance of the output end so that the reference is configurable. Along with the process development of the integrated circuit, power supply voltage is continuously reduced. The invention is very suitable for the integrated circuits of advance process in the future.