A piecewise temperature-curvature compensation bandgap with internal chopper stabilized amplifiers

This paper presented a high-accuracy bandgap reference circuit with novel temperature curvature compensation technology and chopper stabilized technology. The proposed bandgap circuit achieves a good temperature coefficient (TC) without the trimming circuit by high-order adaptive curvature compensation. Besides, we applied the chopper stabilized technology to internal amplifiers in bandgap reference, which reduces the offset voltage of the amplifier and improves output voltage precision and TC. The bandgap circuit has been manufactured in a 180 nm BCD process. The core occupies an active chip area of 160 μm × 370μm. The simulated temperature coefficient is 0.755 ppm/◦C with a wide temperature range of −40 °C∼125 °C. The measurement results indicated that the designed bandgap reference has high precision. The measurement temperature coefficient is 10.07 ppm/◦C. The line regulation of bandgap reference is 0.07 %. Besides, the PSRR of the circuit is −65dB@100 Hz. The current consumption of the circuit is 12.6uA.