A Temperature-Adaptive Low Dropout Regulator Architecture with Dynamic Voltage Scaling for Low Power IoT Applications
Received: 24 May 2025 | Revised: 9 June 2025 | Accepted: 21 June 2025 | Online: 12 July 2025
Corresponding author: R. Pallavi
Abstract
The aggressive scaling of CMOS technologies for Internet of Things (IoT) devices has intensified power management challenges, particularly under thermally stressed and battery-constrained conditions. Elevated temperatures exacerbate leakage and quiescent currents due to reduced gate oxide thickness and increased subthreshold conduction, severely degrading efficiency and system reliability. This work presents a temperature-adaptive Low Dropout (LDO) regulator architecture specifically designed for ultra-low power IoT applications. In contrast to conventional fixed-reference LDOs, the proposed design dynamically adjusts its output voltage based on die temperature using a composite temperature-sensitive reference, synthesized by combining a process-tunable bandgap reference with a Complementary-To-Absolute-Temperature (CTAT) voltage. The designed regulator supports dual-mode operation, providing 1.8 V and 1.2 V from a 2–3.3 V battery supply. The proposed architecture has been simulated and verified using the 45 nm Cadence technology node. Simulation results confirm its temperature-dependent performance, demonstrating a smooth voltage drop from 1.99 V at -40 °C to 1.65 V at 125 °C under a nominal 1.8 V supply. For a nominal 1.2 V output, the voltage scales from 1.27 V to 0.93 V, with 1.13 V at 25 °C. These results substantially outperform conventional fixed-reference LDOs. The proposed architecture is highly relevant for modern IoT edge devices, wearables that demand ultra-low power operation, extended battery life, and consistent performance in thermally dynamic environments.
Keywords:
Low Dropout (LDO) regulator, low leakage current, Complementary-To-Absolute-Temperature (CTAT) voltage, low quiescent currentDownloads
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Copyright (c) 2025 R. Pallavi, D. K. Nayana, K. M. Sudharshan
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