Low-dropout voltage reference: an approach to low-temperature-sensitivity architectures with high drive capability

A modified circuit topology for voltage references capable of providing very high load current with low-temperature-sensitivity output voltage is presented. Employing a proportional-to-absolute-temperature current source and a complementary-to-absolute-temperature voltage source in a novel closed-loop configuration, the output voltage can be tuned over a wide range of voltages lower or higher than the silicon bandgap voltage. These features make the configuration a promising competitor for low-dropout regulators. A possible implementation of the proposed topology in 0.18 mu m technology shows that the simulated 0.9 and 1.3 V voltage references have fast and stable operation for load currents up to 100 mA. The temperature coefficient for both design cases is smaller than 37 ppm/degrees C.