Voltage reference source circuit and method for generating voltage reference source

The invention relates to an integrated circuit and discloses a voltage reference source circuit and a method for generating a voltage reference source. The method comprises the following steps of: generating a self-adaption nonlinear PTAT (positive temperature coefficient) current through a high-order temperature coefficient compensation circuit; converting the current into a self-adaption nonlinear PTAT voltage and then superposing the voltage with a first-order reference voltage; and generating the reference voltage approximate to zero-temperature coefficient, as the voltage reference source. The self-adaption nonlinear PTAT voltage counteracts the nonlinear negative temperature coefficient in the first-order reference voltage, so the voltage reference source has lower temperature coefficient. In addition, the structure is simple, the compensation branch stability is better and the influence on the initial precision of the voltage reference source is small.