Design of a band gap reference voltage source with accurate segment compensation
A low temperature drift coefficient bandgap reference voltage source was designed to address the problem of high temperature drift coefficient in traditional bandgap reference voltages. The positive and negative temperature coefficient currents were introduced separately to realize linear compensation for the bandgap reference voltage at high and low temperature stages. The NPN transistor serves as a switch transistor, and the NMOS transistor operating in the linear region serves as an equivalent resistor to convert the positive and negative temperature coefficient current into the base voltage, by which the conduction and cutoff of the NPN transistor were controlled, and thereby the temperature range for the compensation was controlled, finally precise compensation was achieved. The simulation was conducted through Cadence based on the SMIC 0. 18 μm process. The simulation results show that when the input voltage is 5 V and the temperature is between -40 ℃ and 125 ℃, the temperature drift coefficient decreases from 16. 48 × 10-6/℃ to 0. 829 × 10-6/℃ after precise compensation of the output voltage. The maximum change in output reference voltage is 152 μV. At room temperature, the power suppression ratio at low frequencies is 73. 7 dB, and the voltage source can operate stably between 2. 8 V and 7. 5 V.
万方数据
维普
