Exploration and Evaluation of Low-Dropout Linear Voltage Regulator with FinFET, TFET and Hybrid TFET-FinFET Implementations.

Abstract

This paper investigates and evaluates analog and digital low-dropout linear voltage regulators (LDO) with FinFET, TFET and hybrid TFET-FinFET implementations. We utilize Sentaurus physics-based atomistic 3D TCAD mixed-mode simulations for device characteristics and HSPICE with look-up tables based on Verilog-A models calibrated with TCAD simulation results. Frequency response, load regulation and power supply rejection ratio (PSRR) are evaluated for analog LDOs under low, medium and high bias-current conditions. The results indicate that for analog implementations, TFET-LDO and hybrid-LDO provide better loop-gain and PSRR than FinFET-LDO under low and medium operating currents, whereas at higher operating current, FinFET implementation would outperform. As operating voltage is reduced, the performances of analog implementations degrade, and digital implementations become favorable for VIN below around 0.55V. We further show that for digital LDO, all FinFET implementation provides superior performance over all TFET and hybrid TFET-FinFET implementations.