Analysis and Design of Low Noise Voltage Regulator With Integrated Single BJT Bandgap Reference Upto 10 mA Loads

This brief presents a low-voltage regulator with an integrated single bipolar-based bandgap voltage reference circuit. Unlike conventional architectures, the proposal has a bandgap core current independent of the load, making it suitable to support a wider range of load currents upto 10mA. The regulator uses an improved self-bias loop to increase the DC gain of the loop. Although the architecture does not use offset canceling techniques like chopping, the circuit has an average accuracy of 23 ppm/
$^{o}\text{C}$
from -40°C to 125°C. Embedding the bandgap core in the error amplifier’s first stage reduces the number of noise sources and yields a lower offset temperature coefficient. This brief also briefly analyzes the negative feedback nature of the self-bias loop. The prototype is designed in TSMC 65nm LP technology and regulates the output voltage of 1V from a 1.2V supply. The measured output noise is about
$10~\mu \text{V}/\boldsymbol {\sqrt {Hz}}$
at 1Hz, and the load regulation is 0.50 mV/mA. The design occupies a silicon area of about 0.0121 mm2 while consuming 0.4mA of bias current.