A high-order bandgap voltage reference (BGR) is designed by adopting a current which is proportional to absolute temperature T1.5. The high-order BGR is analyzed and simulated in SMIC 0.18μm CMOS process. Simulation results show that the designed high-order BGR achieves temperature coefficient of 2.54ppm/°C when temperature ranging from-55°C to 125°C. The high-order BGR at 10Hz, 100Hz, 1kHz, 10kHz and 100kHz achieves, respectively, the power supply rejection ratio of-64.01dB, -64.01dB, -64dB, -63.5dB and-53.2dB. When power supply voltage changes from 1.7V to 2.5V, the output voltage deviation of BGR is only 617.6μV.

This paper designs a high-gain wide-bandwidth multistage amplifier by employing the dual-miller compensation with nulling-resistor and dual-feedforward compensation (DMCNR-DFC) in 0.35μm BCD process. The designed DMCNR-DFC multistage amplifier achieves well performance including gain-bandwidth product (GBW) and slew rate (SR). Simulation results show that the DMCNR-DFC multistage amplifier achieves a dc gain of about 121.1dB and GBW of about 6.1MHz with 52o phase margin.

In this paper, a low temperature coefficient bandgap voltage (BGR) is designed for A/D converter by adopting piecewise-linear compensation technique. The designed BGR is analyzed and simulated in SMIC 0.18μm CMOS process. Simulation results show that the PSRR of the designed BGR achieves-72.51dB, -72.49dB, and-70.58dB at 10Hz, 100Hz and 1kHz respectively. The designed BGR achieve the temperature coefficient of 1.57 ppm/°C when temperature is in the range from-35°C to 125°C. When power supply voltage VDD changes from 1V to 7V, the deviation of the designed BGR output voltage VREF is only 4.465μV.