A Segmented Compensation Wide Operating Range Bandgap Reference Voltage Source

In this paper, the problem of high temperature drift coefficient of traditional bandgap reference output voltage is addressed. A precise segmented compensation method is proposed: first, positive temperature coefficient current and negative temperature coefficient current are introduced to compensate for the curvature of the reference voltage in the high and low temperature stages, respectively. Using resistance series voltage division to convert positive and negative temperature coefficient currents into BJT base voltage, controlling the conduction and cutoff of BJT tubes. Enable the BJT tube to serve as a switch to control the temperature range at which segmented compensation begins and ends. On the basis of this method, a low-temperature drift coefficient reference source was designed using SMIC 180nm CMOS technology. The simulation verification in Cadence software shows that under a 5V power supply voltage, the temperature drift coefficient of the compensated output voltage is 0.826ppm/°C, which reduces the temperature drift coefficient by 25times. The PSR of the output voltage is 62.63dB at low frequencies. When the power supply voltage is between 2–6V, the reference source provides a stable voltage of 1.15V.