کنفرانس بین المللی میکروالکترونیک ایران

صفحه اصلی / پنجمین کنفرانس بین المللی میکروالکترونیک ایران

Double-OTA External Capless Low-power LDO Regulator with Enhanced PSR and Transient Response

نویسندگان :

Mohammad Ahmadi¹ Emad Ebrahimi²

1- IC Design Research Lab, Electrical Engineering Department, Shahrood University of Technology 2- IC Design Research Lab, Electrical Engineering Department, Shahrood University of Technology

کلمات کلیدی :

External capacitor-less LDO،fast transient،low drop-out (LDO) regulator،power supply rejection (PSR)

چکیده :

Low drop-out (LDO) regulators play a vital role in power management systems, serving as a critical component. This research paper introduces an innovative LDO regulator that offers enhanced power supply rejection (PSR) and load transient response. In the proposed LDO, by using two OTAs as error amplifiers in a complementary scheme and transferring effectively the over/undershoot of the output voltage to their Tail transistors, the bias current of each OTA is modulated dynamically to improve the load transient response and slew rate. Besides, creating a zero by a low pass filter in the voltage supply terminal of the first error amplifier is caused to reduce the effect of the pole located in the gate of the pass transistor, which results in the improvement of the output PSR. These zeroes made the proposed LDO stable without any external off-chip capacitor with a phase margin of 60 degrees. The proposed design with an input voltage of 1.8 to 2.4 volts has a PSR of -69 dB at a frequency of 1 kHz. Also, the quiescent current of the LDO is as low as 600 nA, while delivers maximum current of 50 mA to the load.