An Improved Reference Voltage Circuit Design

In this paper, an improved reference voltage circuit has been proposed. Unlike the traditional works, in the proposed circuit, the positive temperature coefficient voltage is obtained from the BJT but the negative temperature coefficient voltage is from the weak-inversion biased MOSFETs. Proper combination of the positive and negative temperature-coefficient voltages, a zero temperature-coefficient reference voltage can be given. The proposed reference voltage has been layout by using the 2P4M 0.35 mu m process parameters. According to the post-layout simulation results, when the supply voltage is 1.7 V, the corresponding power consumption is 24.18 mu W, the output reference voltage can be around 488 mV, and as the temperature varies from -20 degrees C to 120 degrees C, the temperature coefficient of the proposed reference voltage is only 8.336 ppm/degrees C. As compared to the traditional works, the proposed circuit benefits from simpler circuit architecture, less chip area, and smaller temperature coefficient. The proposed reference voltage circuit can be applied to various analog integrated circuits applications.